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City of Hamilton Public Health Services 2011 Vector Borne Diseases Report

For: The Ministry of Health & Long-Term Care and Public Health Ontario February 2012


ACKNOWLEDGEMENTS

We wish to acknowledge all of our partners, external and internal to the City of Hamilton, for their participation in Vector-Borne Disease (VBD) surveillance, prevention and control during the 2011 VBD season. External: Annette Tavares, Contract Biologist - WNV Consultant and Trainer Central East WNV Working Group (includes some Central West health units) Cosray Labs, adult mosquito identification and viral testing contractor (20052007, 2008 -2011) McMaster Institute of Environment and Health (MIEH) Ontario Ministry of Health and Long-Term Care and Public Health Ontario VBD Program Staff Pestalto Environmental Health Services Inc, Larviciding contractor (2008 – 2011) Internal City of Hamilton Programs or Departments: Customer Contact Centre Finance and Administration GIS (Geographic Information Systems) Services Human Resources Public Health Services Public Works Department Purchasing This report was coordinated by Natasha Mihas, Environmental Health Promoter, and Susan Harding-Cruz, Manager, Vector Borne Diseases, with input by: Carole Craig (Epidemiologist, Surveillance Unit) Shane Thombs (GIS Technologist, GIS Services) Carolyn Bannon (Public Health Inspector, Vector Borne Diseases) Ioana Lupascu (Public Health Inspector, Vector Borne Diseases) Aimei Fan (Health Analyst, Surveillance Unit) Dawei Wang (Health Analyst, Surveillance Unit) Marie McKeary (Research Facilitator, McMaster Institute of Environment and Health) Kelly-Anne Colling (Public Health Inspector, Infectious Disease Team) Debra Marsillo (Public Health Inspector, Infectious Disease Team) Julie Trevisan (Public Health Inspector, Infectious Disease Team) In consultation with: Michelle Baird (Manager, Infectious Disease Team) Nancy Greaves (Manager, Surveillance Unit) Rob Hall (Director, Health Protection Division) Dr. Chris Mackie (Associate Medical Officer of Health) Dr. Adriana Dragan (Public Health Physician)

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PREFACE.............................................................................................................5 EXECUTIVE SUMMARY ......................................................................................6 1.0

INTRODUCTION.......................................................................................13

2.0

HUMAN CASE SURVEILLANCE .............................................................17

2.1 West Nile Virus.............................................................................................................................. 17 2.1.1 Highlights.................................................................................................................................... 17 2.1.2 Methods....................................................................................................................................... 17 2.1.3 Results, Trends and Comparisons............................................................................................... 17 2.2 Lyme Disease ................................................................................................................................. 18 2.2.1 Highlights.................................................................................................................................... 18 2.2.2 Methods....................................................................................................................................... 18 2.2.3 Results, Trends and Comparisons............................................................................................... 19 2.3 Other Vector Borne Diseases........................................................................................................ 20 2.3.1 Highlights.................................................................................................................................... 20 2.3.2 Methods....................................................................................................................................... 20 2.3.3 Results, Trends and Comparisons............................................................................................... 20

3.0

WILDLIFE SURVEILLANCE ....................................................................22

3.1 West Nile Virus.............................................................................................................................. 22 3.1.1 Highlights........................................................................................................................................ 22 3.1.2 Methods........................................................................................................................................... 22 3.1.3 Results, Trends and Comparisons................................................................................................... 22 3.2 Lyme Disease ................................................................................................................................. 23 3.2.1 Highlights........................................................................................................................................ 23 3.2.2 Methods........................................................................................................................................... 23 3.2.3 Results, Trends and Comparisons................................................................................................... 23 3.3 Other Vector Borne Diseases........................................................................................................ 23 3.3.1 Highlights........................................................................................................................................ 23 3.3.2 Methods........................................................................................................................................... 23 3.3.3 Results, Trends and Comparisons................................................................................................... 23

4.0

VECTOR SURVEILLANCE ......................................................................24

4.1 West Nile Virus.............................................................................................................................. 24 4.1.1 Adult Mosquito Surveillance ....................................................................................................... 24 Highlights______________________________________________________________________ 24 Methods_______________________________________________________________________ 25 Results, Trends, and Comparisons ________________________________________________ 28 4.1.2 Larval Mosquito Surveillance ..................................................................................................... 35 Highlights______________________________________________________________________ 35

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Methods_______________________________________________________________________ 35 Results, Trends, and Comparisons ________________________________________________ 36 4.2 Lyme Disease Surveillance............................................................................................................ 38 4.2.1 Highlights........................................................................................................................................ 38 4.2.2 Methods........................................................................................................................................... 38 4.2.3 Results, Trends, and Comparisons.................................................................................................. 38 4.3 Other Vector Borne Diseases........................................................................................................ 39 4.3.1 Highlights........................................................................................................................................ 39 4.3.2 Methods........................................................................................................................................... 39 4.3.3 Results, Trends, Comparisons......................................................................................................... 40

5.0

CONTROL MEASURES ...........................................................................41

5.1 West Nile Virus Control....................................................................................................................... 41 5.1.1 Highlights........................................................................................................................................ 41 5.1.2 Methods........................................................................................................................................... 41 5.1.3 Results, Trends and Comparisons................................................................................................... 44 5.2

Lyme Disease Control ................................................................................................................... 47

5.3

Other Vector Borne Disease Control ........................................................................................... 47

6.0

RISK ASSESSMENT................................................................................48

7.0

PUBLIC COMMUNICATION ....................................................................54

8.0

EVALUATION...........................................................................................58

8.1 Communication..................................................................................................................................... 58 8.2 Website Analysis and MIEH Program Recommendations ............................................................... 60 8.3 Program Evaluation ............................................................................................................................. 66

9.0 10.0

PROGRAM COSTS ..................................................................................67 CONCLUSION.......................................................................................69

GLOSSARY........................................................................................................71 APPENDICES.....................................................................................................72

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List of Tables Table 1: VBD Program Goals and Accomplishments 2011.................................15 Table 2: Confirmed Reports of Other Reportable Vector-borne Diseases, City of Hamilton, 2011 .............................................................................................21 Table 3: City Of Hamilton Adult Mosquito Trap Locations 2011..........................27 Table 4: Vector Species Abundance Totals in the City of Hamilton, 2011 ..........29 Table 5: 2011 Hamilton Positive Traps - By Trap Location ................................32 Table 6: Test results for all thirty-one WNV-positive pools by Trap Week ..........33 Table 7: Hamilton Positive Traps – 2002-2011* and Predicted Traps 2011.......34 Table 8: Monitored potential mosquito breeding sites and proportion of sites treated, City of Hamilton, 2011 .....................................................................37 Table 9: Roadside and Non-Roadside Catch Basin Treatments, Dates and Product Use for the City of Hamilton in 2011................................................45 Table 10: Non-Roadside Catch Basin Treatments, Dates and Product Use for the City of Hamilton in 2011 ...............................................................................45 Table 11: Recent Catch basin Treatments 2006 - 2011......................................46 Table 12: 2011 Pestalto Treatment and Monitoring Summary............................47 Table 13 Risk Assessment Meetings or Risk Summaries and Risk Level .........49 Table 14: 2011 Chronological Order of Communication Campaign- Education and Outreach Activities ................................................................................55 Table 15: Tick Evaluation Results, City of Hamilton 2011...................................59 Table 16: Targeted Web Pages within WNV Website, 2010 & 2011..................61 Table 17: Number of Targeted Hits by Month in 2010-2011 ..............................62 Table 18: Annual Top Three Targeted Hamilton WNV Pages, 2009 to 2011.....62 Table 19: Adult Mosquito Public Registry Website Hits 2009 - 2011 .................63 Table 20: Comparison of Treatment Costs, 2003-2011 ......................................68 List of Figures Figure 1: WNV infectivity rate among the adult vector Culex species mosquitoes compared to human cases of WNV, 2002 – 2011. .........................................7 Figure 2: WNV human cases 2002-2011, City of Hamilton compared to Ontario .....................................................................................................................18 Figure 3: Yearly Human Cases of Lyme disease ................................................19 Figure 4: Mosquito Natural Habitats and other land classifications overlaid with 2011 Mosquito Traps and Treated Mosquito Breeding Areas* .....................25 Figure 5: Weekly median number of Culex pipien/restuans mosquitoes per trap .....................................................................................................................30 Figure 6: Weekly median number of mosquitoes per trap..................................30 Figure 7: Potential Mosquito Breeding Areas (water sites) Monitored and Treated in 2011 ............................................................................................37 Figure 8: Tick submissions found on human hosts, City of Hamilton, 2007 – 2011 .....................................................................................................................39 Figure 9: Catch Basin Treatment Areas (2011) ..................................................42 Figure 10: WNV Public and Private Standing Water Complaints 2011 ...............46

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Preface Mosquitoes are not new to Hamilton. These insects have been a nuisance and have had the capacity to transmit disease to people in the community for many years. The excerpt below, from a presentation at one of Hamilton’s Head-ofthe-Lake Historical Society meetings, which is included in the publication, Wentworth Bygones, Volume 5, relates a story about mosquitoes, nuisance and disease from the early 1800’s. Thankfully Hamilton has changed from those days and disease transmission and control are also much better understood. “The Beginnings of the History of Hamilton By T. Roy Woodhouse (An Address to the Society on April 10, 1959) The Beginnings of Hamilton are rather nebulous, but as far as known records exist they indicate that the year 1813 seems to be the best choice, because that was the year when George Hamilton became the first person in Barton Township to divide part of his farm into town lots. Prior to this, the settlers had been thinking of their lands only in the terms of farm land- and not very attractive farm land at that……………………………………….. ……………….Furthermore, the land below the mountain was covered by dense forest, and by saw-grass that cut travellers’ clothes to ribbons unless buckskin was worn, and by swampy stagnant low-lying areas that, according to ancient belief, gave off foul odors and a miasma that caused Ague, or shakes, or the summer complaint, or the prevailing sickness, as it was variously called. The Ague was a most unpleasant, weakening sickness which the settlers tried to avoid by choosing high ground in preference to low lands. Of course the doctors knew all about the disease. One famous pioneer doctor described it as follows: The cause of Feaver is the unfavourable qualities of the air and the ailment. The excessive heat of the season puts the vapours or exhalations into an over-rapid motion, and the air was so rarified that we do not suck in a sufficient amount of it, and the small quantity we did receive was loaded with insects and corpusculums, which the fatal necessity of respiration obliged us to swallow, and by this means Nature was put into a disorder. The use of Brandy and salt meat soured the blood, and this sourness occasioned a sort of coagulation of the chyle and the blood, and this coagulation hindered the circulation through the heart with a due degree of celerity and thereupon there ensued an extraordinary fermentation, which is nothing else but a Feaver. You see, it is all quite simple. Unfortunately, the doctors did not know how to cure this “Feaver”. To us today, with our greatly expanded medical knowledge, it seems odd that noone ever suspected mosquitoes, because in those days they really had mosquitoes – big ones that could bite through a two inch plank- vicious ones that would glare at you through a window and gnash their teeth in rage when they found that they could not reach you……….. Is it any wonder that most settlers avoided the lands below the mountain? ………”

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EXECUTIVE SUMMARY The Vector Borne Diseases (VBD) program for the City of Hamilton continues to conduct many activities in order to assess and control West Nile Virus (WNV), Lyme Disease, Eastern Equine Encephalitis (EEE) virus and other reportable vector borne diseases, as defined by Ontario Regulation 559/91, Specification of Reportable Diseases, made under the Health Protection and Promotion Act. The goal of the VBD program is to reduce the risk of vector borne disease transmission to humans using Best Management Practices (BMP) within an Integrated Vector Management (IVM) program, in keeping with Ontario’s West Nile Virus Preparedness and Prevention Plan. In 2011 the West Nile virus component of the VBD program was audited by City of Hamilton Audit Services and the outcome was for the program to complete outstanding policies and procedures and to conduct a program evaluation within 12 to 18 months of the audit period. This work began in 2011 and will be completed in 2012. This report presents surveillance findings as well as program updates from the 2011 season. West Nile Virus The 2011 season was marked with a significant increase in WNV activity, both locally and in Ontario. This increase was evident as Ontario recorded 279 positive mosquito pools, the third highest number since mosquito surveillance began in 2001, and a mosquito infection rate of 4.7 (minimum per 1000 tested). At a local level, the City of Hamilton mirrored this increase with an infection rate of 7 (minimum per 1000 tested), the second highest since the programs’ inception (see Figure 1). The number of human WNV cases also spiked this season with 71 confirmed cases in Ontario. However, these events did not correspond to a considerable rise in human cases in Hamilton. On the other hand, the trend in mosquito WNV infectivity rate since the introduction of the virus remains similar to the trend in the onset of human cases (see Figure 1). Hamilton Public Health Services (PHS) investigated two confirmed WNV cases; exposures for both cases were determined to be from within the City of Hamilton. An additional two cases of WNV were also investigated, which did not meet provincial case definition.

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Human cases of West Nile virus illness compared to Culex spp. adult mosquito WNV infectivity rate (pooled), City of Hamilton, 2002 - 2011. Mosquito WNV infectivity rate (pooled, mosquito season only) Mosquito WNV Infectivity Rate

25 20 15 10 5

WNV Human Cases

0

20 18 16 14 12 10 8 6 4 2 0

WNV Human Cases 18

4

3 0

2002

2003

2004

1

2005

2006

1

1

2007

2008

2 0

0

2009

2010

2011

Year of Symptom Onset / Mosquito Collection

Figure 1: WNV infectivity rate among the adult vector Culex species mosquitoes compared to human cases of WNV, 2002 – 2011. Accumulated Degree Days (ADD) continued to be monitored by the province in 2011. Hamilton exceeded 200 ADD, a threshold that has been found to be associated with a higher risk of human cases. Past seasons also exceeded 200 ADD, in 2007 and 2010, however there was one human case in 2007 and none in 2010. In 2011, a marked difference from those years was the higher temperatures for the month of July. This month also lacked precipitation most days but regular rain events returned in August. The WNV program uses local risk level guidelines for low, moderate, and high risk. By early September local risk moved to high based on Hamilton meeting one or more (Hamilton had all) of the following: √ Multiple WNV-positive mosquito pools in areas of significant human activity √ First human WNV case in Hamilton √ Pattern of human cases in adjacent health units 7


√ Other considerations indicating peak risk for human WNV infection, including more than 200 ADD. In addition the Culex mosquito remains the main species of concern for WNV in Hamilton. The City of Hamilton also confirmed three other positive WNV vector species in 2011: Anopheles quadrimaculatus, Ochlerotatus triseriatus, and Ochlerotatus japonicus. After Week 31 when eight positive pools with four positive mosquito species were identified, season-to-date data was analysed in order to predict which further traps would capture positive mosquitoes in the season. These results were used in combination with other risk information to target control efforts. Of the 15 traps identified as likely to capture positives during the 2011 season, 67% (10 traps) did capture WNV infected mosquitoes. For the risk assessment meetings, Geographic Information Services (GIS) staff recommended the use of Features Manipulation Engine software in order to display weekly adult mosquito trap data using Google Keyhole Markup Language (KML). This was incorporated into the meetings and was also recommended to other health unit jurisdictions in Ontario as a useful visual tool (see Appendix C). Lyme Disease In 2011, Ontario saw an increase in Lyme disease activity. PHS investigated three individuals for Lyme disease: one did not meet case definition, and two were classified as confirmed and were likely acquired within the province, at Turkey Point. Of the 38 ticks submitted for identification by Hamilton residents, three were Ixodes scapularis (black-legged ticks). One additional tick result submitted to the Central Public Health lab is pending. The three known black legged ticks were tested for Lyme disease and all were negative on PCR for Borrelia burdorferi. Two of the ticks were acquired within the province but outside of Hamilton and one was acquired while travelling in New York State. Hamilton’s’ Lyme Disease Contingency Plan, developed in 2010, outlines various triggers that would increase PHS’ surveillance activities from passive to active. In 2011, Hamilton did not meet any of the triggers to require active tick surveillance and as a result, a passive tick surveillance program remained in place.

Other Vector Borne Diseases In 2011, the MOHLTC requested that health units modify their mosquito surveillance program to incorporate identifying and testing vectors of the Eastern Equine Encephalitis (EEE) virus. This request was due to the increase of EEE

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activity in Ontario in 2010 and was to determine the extent of the virus in Ontario’s’ mosquito population. Of the 616 viral tests completed in 2011, zero pools were positive for the EEE virus. Culiseta melanura, a mosquito of concern for transmission of EEE, was captured in two pools in two different trap locations but tested negative. Nine cases of malaria were reported to Hamilton Public Health Services during 2011. All cases were reported as immigration or travel related to other countries. There were no cases of plague, tularemia, or yellow fever reported in Hamilton for 2011. Risk Assessments As mandated by Ontario Regulation – O.R. 199/03, “The Control of West Nile Virus”, Hamilton PHS conducted regular, local risk assessment meetings to discuss the status of WNV, Lyme disease and other reportable vector-borne diseases in Hamilton. Based on the heightened WNV activity outlined in this report, Hamilton moved from low risk to moderate risk on August 10th and to high risk on September 8th, 2011. Public Communication In 2011, Hamilton PHS’ communication plan incorporated a strategic multilayered approach that included communication to individuals, networks, organizations and communities through mass media, interpersonal communication and events. A three phase communication plan was developed to determine when and what type of activities would be implemented throughout the season. As risk to human exposure increased, various phases were implemented. Risk was measured by the presence of positive mosquito pools and positive human cases based on local risk guidelines (outlined in the risk assessment section of this report). Communication activities implemented in 2011 included posting current information on the PHS website and through media releases, outdoor bus advertisements, a Seniors Review (magazine) advertisement, and radio advertisements on four local stations, alternating on a weekly basis. Furthermore, staff attended three community events to allow for interpersonal communications with the public. Due to the high number of mosquito pools found positive with WNV, additional activities were implemented in August and included an extended radio advertisement schedule, advertisements in the five local Community Newspapers, and staff attending a fourth community event in September. A WNV tip sheet was also created outlining key preventative messages and was provided with existing resources to the public.

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Messaging about preventing Lyme disease was also incorporated in the WNV radio and print ads. PHS staff also educated the public at the four community events on what Lyme disease is, how it is acquired and preventative measures. A Lyme disease fact sheet was also created in 2011 (see Appendix F). Evaluation As mentioned earlier, the WNV program was audited in 2011. Program evaluation was identified as an area lacking in the WNV program as an evaluation had not been conducted since 2004/2005. Steps were taken in 2011 to begin to scope and develop a program evaluation framework. This evaluation will be completed in 2012. In terms of evaluating WNV communication strategies, a tool was developed and implemented at the final community event in 2011. This tool was to determine the publics’ opinion of their preferred media to receive health information; and more specifically their preferred local radio station. This tool also inquired if and how WNV messaging was received throughout the season. PHS staff surveyed 212 individuals over the three day event. Of these, 183 or 86% believed that radio was an effective method to communicate health information. PHS also used an evaluation tool at all four community events to determine the publics’ knowledge and awareness level of Lyme disease, the diseases’ connection to ticks, and whether people saw ticks of any kind within the City of Hamilton. The results indicated that 79% of individuals had heard of Lyme disease; 61% knew Lyme disease was caused by ticks; 57% knew what a tick looked like; and 82% indicated they had not seen ticks in Hamilton. Of those who had, Glanbrook (including Binbrook) and Stoney Creek (including Winona) were areas mentioned most; followed by Dundas. Program Costs The communication and contractual costs associated with the development and execution of the VBD program in 2011 were: ƒ Communication – $31,000 ƒ Contracted Adult mosquito identification and viral testing – $42,332 ƒ Contracted Larval mosquito treatment - $217,588 Costs associated with larval and adult mosquito surveillance, performing investigations and enforcement of the standing water by-law, program costs for

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supplies and equipment, as well as direct staff costs, are submitted to the MOHLTC through routine reporting.

Conclusions In 2011 WNV activity increased locally and provincially. There were 31 positive adult mosquito pools and two human cases for Hamilton; Ontario reported 279 positive adult mosquito pools and 71 human cases. For Hamilton, the increased activity in positive mosquitoes triggered an increase in mosquito control and communication outreach in order to prevent potential disease transmission and to help reduce local risk. Increased efforts included adding a fourth round of larviciding of city catch basins and extending the WNV radio campaign further into August and September to share personal protection messages with the community. A fourth community event, the Binbrook Fair, was also attended in October to share protection messages. These activities were part of Hamilton’s Best Management Practices within the Integrated Vector Management (IVM) program. The 2011 season was also a time to consider reviewing the program and two options were to put forward: to perform a situational assessment or conduct a program evaluation. The program evaluation was chosen as the tool to evaluate the program as it was a recommendation from the internal audit. The West Nile Virus component of the Infectious Disease program audit recommended that outstanding policies & procedures be completed and that an updated program evaluation be conducted. The program evaluation process began in 2011 and will be finished in 2012. The evaluation report is expected to help shape the 2012 and 2013 program activities including setting up a framework for future evaluations. In order to create efficiencies in the program, at the outset of the 2011 season, the Surveillance Unit team changed how they would compile and present data at the regular risk assessment meetings. Data was compiled and shared based on the local risk so that fewer graphs, charts, and figures were produced while WNV activity remained low with the plan to increase and tailor surveillance data as needed when activity increased. As of Week 31 when 8 positive adult mosquito pools were identified, the Surveillance Unit team responded with additional products to help assess local risk. For the 2011 season, GIS staff also incorporated a new method to display the adult mosquito trap data versus static pie charts of each trap on a map. Through the joint purchase by Surveillance Unit and the West Nile virus program (Vector Borne Diseases program) of a Features Manipulation Engine license, GIS staff were able to present the mosquito trap data using Google Earth. This new method allowed mosquito trap data and habitat information to be presented on the map (on the map directly or in pop up format) per trap location.

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Although the 2011 saw increased viral activity, in Hamilton and across Ontario, it remains a challenge to predict future seasons. Theories for increased viral activity include mild winters preceding a wet spring or bird populations may fluctuate impacting the reservoir for the virus. Hamilton PHS recommends health units continue to maintain a comprehensive mosquito monitoring, control, and education program to be prepared for changes in WNV or other mosquito borne disease activity year to year. For Lyme disease surveillance, Hamilton did not confirm any evidence of local activity in ticks or people although acquiring Lyme Disease within Ontario remains an ongoing threat. In the spring of 2012 the VBD staff will participate in a training exercise to practice field surveillance in a known endemic area of Ontario. The focus of the 2012 VBD program will be to operate a comprehensive program more efficiently (reductions were made to the 2012 budget), continue to review and refine the risk assessment process, and to implement program evaluation recommendations, once known.

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1.0 INTRODUCTION The City of Hamilton’s Vector Borne Disease (VBD) program has monitored the progression of West Nile Virus (WNV) in North America since it was first detected in 1999, in New York City. The City of Hamilton’s WNV surveillance program began in the late summer of 2000 with dead bird surveillance, at the request of the Ministry of Health and Long-Term Care (MOHLTC). Since then the program has developed further to identify WNV activity in Hamilton through extensive surveillance activities that include the identification and testing of mosquitoes and the investigation of reported human cases. Surveillance data collected are mapped throughout the season via geographic information systems (GIS) to allow for the monitoring and identification of trends of WNV activity, in the City of Hamilton. Additionally, the City of Hamilton conducts a seasonal mosquito control program as well as developing a strategic communication plan and public awareness campaign each season. Various components of the WNV program are contracted to external sources. These contractors are listed in Appendix A. In addition to the extensive WNV program, Lyme disease surveillance has expanded over the past few years. Hamilton Public Health Services (PHS) monitors the presence of Lyme disease in Hamilton through passive surveillance activities that include the submission of ticks received by the public for identification and testing of Borrelia burgdorferi bacteria, specifically in Ixodes scapularis (black-legged ticks). Hamilton’s’ Lyme Disease Contingency Plan, developed in 2010, outlines various triggers that would increase PHS’ surveillance activities from passive to active. In 2011, the MOHLTC requested that health units modify their mosquito surveillance program to incorporate the identification and viral testing of vectors of the Eastern Equine Encephalitis (EEE) virus. This request is due to the recent increase of EEE activity in Ontario in 2010 and also to determine the extent of the virus in Ontario’s’ mosquito population. Hamilton followed the request and included all EEE recommended tests. Other reportable vector-borne diseases of concern include tularemia, malaria, yellow fever and the plague, as mentioned by the MOHLTC in a 2008 letter to health units. The VBD program reviews global surveillance data for any indication of an increased likelihood that these diseases may be acquired in Ontario. Additionally, PHS has requested McMaster Institute of Environment and Health (MIEH) to provide updates, if needed, on links between climate change and emerging vector borne diseases, including the potential for locally acquired

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malaria. Appropriate measures will be taken if these diseases emerge as a local threat in Hamilton. The VBD program typically reviews the mosquito surveillance and control programs at the outset and conclusion of each season (April and October/November) through meetings with VBD staff or at WNV Surveillance Unit meetings. These meetings help to: guide what goals to achieve in the upcoming season and future seasons, determine efficiencies, plus decide how best to monitor and assess local risk. The goals for 2011 and related accomplishments are outlined in Table 1. This report outlines the components of the 2011 VBD program and provides detailed information on Hamilton PHS’ human, wildlife and vector surveillance activities. Information regarding control measures, risk assessment criteria and public communication efforts are included. Furthermore, this report evaluates various components of the VBD program and outlines the costs associated to implement the program.

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Table 1: VBD Program Goals and Accomplishments 2011 Goal WEST NILE VIRUS Reduce risk of WNV transmission to humans

Consider new methods to display, compile and review WNV data

Maintain surveillance for adult mosquitoes

Update, monitor and control the standing water sites/breeding habitats on surface waters on public lands

Investigate and respond to public and private land standing water complaints for the enforcement period under the by-law. Take enforcement action using the Standing Water By-law 03-173. Public lands remediated if feasible and within budget constraints or those sites would be treated.

Maintain catch basin treatment with three rounds to provide control in June, July, and August.

Maintain and update local website for West Nile virus including continued upkeep of

Accomplishment Surveillance, monitoring and control of water sites, enforcement of the Standing Water by-law, ongoing risk assessment, communication, education and outreach were all conducted. These major activities have likely helped reduce human risk as Hamilton recorded only two confirmed human cases. A fourth round of catch basin treatments, increased radio advertising, and attendance at a fourth festival helped to provide additional control as well as increase the amount of personal protection measures to help further reduce local risk. GIS staff recommended the use of Features Manipulation Engine software in order to display adult mosquito trap data using Google Earth and this was incorporated into the meetings (see Appendix C). The Surveillance Unit also created efficiencies for their WNV program work by compiling outputs for risk assessment based on risk factors so that fewer outputs were provided during low risk and were increased and adapted based on increasing WNV positive activity. Surveillance and monitoring of 42 adult mosquito traps throughout the season from June to October (weekly) which continues to be amongst the highest number of traps among Central East and Central West area Health Units. However, in Week 40 and 41, the number of traps was reduced from 42 to 29 for staffing efficiencies. Approximately 400 sites continued to be monitored for larval activity by Public Health Services staff which resulted in 942 surveillance visits and 73 sites referred to the larviciding contractor. There were 193 treatments covering a total area of 450,719 square metres, using VectoBac 200G, VectoLex CG or VectoBac 1200L. Public Health Inspectors and seasonal staff investigated 107 complaints from April 1 to October 31st, 2011. Three Orders under the by-law were issued; one Order resulted in a pool on private property being decommissioned with the cost added to the tax bill. Referrals were made to Public Works and sites were remediated where possible although this was limited in 2011. The larviciding contractor treated all other sites that could not be remediated. The majority of catch basins were larvicided at approximately 21 day intervals with methoprene pellets (Altosid Briquets) as per label directions. Due to the increased positive activity (adult mosquito traps), four rounds were conducted for a total of 183,261 treatments (approximately 38,000 per round) . Selected catcbhasins were treated with methoprene briquets for extended treatment (due to access and safety issues). Routine additions to the websites occurred on a monthly basis or as needed. Additions included but were not limited

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Goal

Accomplishment

electronic adult mosquito registry to track all persons within the City who wish to be notified in the event that we undertake spraying/adulticiding for adult mosquito control

to: ƒ West Nile virus larval treatment information and completion dates ƒ Surveillance statistics (positive mosquito traps) ƒ Invitation to be added to the adult mosquito registry (No adulticiding has occurred in Hamilton to date including 2011) In 2011 the WNV team (management and staff) participated in summer events, fairs and presentations, radio messaging, knowledge transfer, and continued website development and McMaster Institute of Environment and Health (MIEH) analyzed traffic on the VBD website. Presentations by staff combined both West Nile Virus and Lyme disease information and included mosquito control, how to reduce the risk of acquiring disease, tick identification, risk behaviours, indicators of disease, and the importance of early detection.

Communication and outreach campaign and evaluation.

Review surveillance data at risk assessment meetings to determine ongoing risk to humans Participate in internal Infectious Disease audit with a review of the West Nile virus program components LYME DISEASE Lyme disease tick collection and identification

Maintain and update local website for Lyme Disease information. Tick database update OTHER VECTOR BORNE DISEASES Program staff were to monitor for other emerging vector borne diseases

Staff developed a simple knowledge and awareness tool for festivals to evaluate public awareness about ticks and Lyme disease. New promotional material was developed as well as information materials. Additional radio advertising was added to run for August and early September in response to the increased risk of WNV following Week 31 when eight positive mosquito pools were identified across the City. Staff also attended a fourth festival to provide personal protection messages. In 2011 the method to review and display surveillance data changed. The audit was conducted and the results were to develop necessary policy and procedures and to conduct a program evaluation over 2011 to 2012. Work began for both before the end of 2011. Staff received ticks for identification and shipped them to the Central Public Health lab if likely to be a black legged tick (deer tick) and only if found on a person. Of 38 ticks received by the program, three (3) were identified as Blacklegged or Ixodes scapularis with one more tick pending identification by the CPHL. For the three black legged ticks, two were acquired within the Province but outside of Hamilton, and one was in New York state. All were negative by PCR for the presence of Borrelia burgdorferi. Routine additions to the websites were conducted on a monthly basis or as needed. The tick database review began in 2011 with plans for a new database as a priority project in 2012. Staff received and reviewed internal surveillance unit reports on diseases reported and investigated by the Infectious Disease team. Malaria cases were reported but none were locally acquired.

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2.0 HUMAN CASE SURVEILLANCE 2.1

West Nile Virus

2.1.1 Highlights In 2003, the Ontario MOHLTC first deemed WNV a reportable and communicable disease under the Health Protection and Promotion Act, R.S.O 1990, Regulations 559/91 and 558/91. Case classification of WNV is based on the provincial case definition provided in Appendix B of the Infectious Diseases Protocol 2009, under the Ontario Public Health Standards. The three clinical pictures are, “WNV Non-Neurological Syndrome”, “WNV Neurological Syndrome” and “WNV Asymptomatic Infection”. 2.1.2 Methods As with all reportable diseases, any health care professional suspecting such illness must report to the local Medical Officer of Health. Reportable diseases in Hamilton are reported by a physician based on clinical suspicion or by laboratories based on the positive results of diagnostic tests. In Hamilton surveillance activities include: 1. Physicians and hospitals report suspect, probable and confirmed cases to our local MOH 2. Canadian Blood Services tests blood and blood product donations for WNV and reports any positive results to the MOH. 3. The Ontario Public Health Laboratory (OPHL) reports positive WNV results to the ordering physician and the local MOH. 2.1.3 Results, Trends and Comparisons Since the introduction of WNV into the local area, the City of Hamilton experienced a high of 15 confirmed and three probable cases in 2002 (including one death). Treatment of catch basin vector breeding areas began in June of 2003. This same year, there was a dramatic decrease to four human cases followed by a few cases in subsequent years, as illustrated in Figure 2. The local trend of decreasing cases mirrors that of the province. There were no human cases of West Nile virus illness reported to Public Health in 2009 and 2010. In 2011, Hamilton PHS investigated two confirmed WNV cases. The exposures for both cases were determined to be from within the City of Hamilton. There were 71 human cases in Ontario.

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20 18 16 14 12 10 8 6 4 2 0

WNV Human Cases Ontario Human Cases

450 400 350 300 250 200 150 100 50 0

Ontario Case Count

Hamilton Case Count

Annual trend of human cases* of West Nile virus illness, Hamilton compared to Ontario, 2002-2011

2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 *confirmed and probable Year of Symptom Onset Source: WNV Human Case Datebase and Ontario Ministry of Health and Long-Term Care integrated Public Health Information System database. Prepared by: City of Hamilton Public Health Services Data Extracted: 2011-12-06

Figure 2: WNV human cases 2002-2011, City of Hamilton compared to Ontario Hamilton Public Health Services investigated an additional 2 cases of WNV in 2011, which did not meet provincial case definition.

2.2

Lyme Disease

2.2.1 Highlights Currently the risk of human infection with Lyme disease in Hamilton remains low. As a result, there have been no actions for field surveillance at the local level although practice sessions may occur in the 2012 season led by Public Health Ontario staff using an endemic area in Ontario.

2.2.2 Methods As with all reportable diseases, any health care professional suspecting such illness must report to the local Medical Officer of Health. Reportable diseases in Hamilton are reported by a physician based on clinical suspicion or by laboratories based on the positive results of diagnostic tests.

18


In Hamilton surveillance activities include: 1. Physicians and hospitals report suspect, probable and confirmed cases to our local MOH. 2. The Ontario Public Health Laboratory (OPHL) reports positive Lyme disease results to the ordering physician and the local MOH. Diagnostic testing for Lyme disease in Canada follows a two-step procedure. The sensitive ELISA test is first used as a screen and, if the results are positive, it is followed with the Western Blot test. 2.2.3 Results, Trends and Comparisons In 2011, the City of Hamilton investigated 3 individuals for Lyme disease: ƒ 1 did not meet case definition ƒ 2 were classified as confirmed and were likely acquired within the province at Turkey Point. Figure 3 illustrates the trend in confirmed and probable Lyme disease over the past 11 years by the exposure location. There has been only one case of Lyme disease acquired in the Hamilton area over this time period, however, in each year from 2008-2010 there was a single Hamilton resident who acquired Lyme disease from an Ontario exposure. In 2011 there were two positive Lyme disease cases from Hamilton and the exposure for each case is most likely Turkey Point. Yearly human cases of Lyme disease by exposure location, City of Hamilton, 2000-2011. Number of Cases

8

Hamilton Exposure Other Ontario Exposure Travel related

7 6 5 4 3 2 1 0 2000

2001

2002

2003

2004

2005

2006

2007

2008

2009

2010

2011

Year of Symptom Onset (or earliest case-related date) Source: Ontario Ministry of Health and Long-Term Care integrated Public Health Information System database. Prepared by: City of Hamilton Public Health Services. Extracted: 05-Jan-2012.

Figure 3: Yearly Human Cases of Lyme disease

19


2.3

Other Vector Borne Diseases

2.3.1 Highlights While many vector borne diseases exist globally, only those reportable under Regulation 559/91 under the Health Protection and Promotion Act are discussed. These include malaria, yellow fever, plague and tularemia. Other mosquito borne vector borne diseases, such as Eastern Equine Encephalitis (EEE) would also be reportable under the regulation as an Encephalitis (Primary, viral), or if the disease caused Meningitis, acute (viral). Nine cases of malaria were reported to Hamilton Public Health Services during 2011. All cases were reported as immigration or travel related to other countries. There were no cases of plague, tularemia, or yellow fever reported in Hamilton for 2011.

2.3.2 Methods As with all reportable diseases, any health care professional suspecting such illness must report to the local Medical Officer of Health. Reportable diseases in Hamilton are reported by a physician based on clinical suspicion or by laboratories based on the positive results of diagnostic tests. In Hamilton surveillance activities include: 1. Physicians and hospitals report suspect, probable and confirmed cases to our local MOH. 2. The Ontario Public Health Laboratory (OPHL) reports positive, reportable Vector borne disease results to the ordering physician and the local MOH.

2.3.3 Results, Trends and Comparisons Cases identified in Table 2 were travel related (all were malaria). As there were no locally acquired cases of malaria, plague, tularemia, or yellow fever, there were no actions taken for field surveillance at the local level for these diseases.

20


Table 2: Confirmed Reports of Other Reportable Vector-borne Diseases, City of Hamilton, 2011 Disease

Agent

Malaria

Plasmodium ovale Plasmodium vivax Plasmodium Falciparum Yersinia pestis Francisella tularensis Yellow fever virus

Plague Tularemia Yellow Fever Total

Number of Confirmed Reports 1* 2* 6* 0 0 0 9

Data Source: Ontario Ministry of Health and Long-Term Care integrated Public Health Information System (iPHIS) database. Data Extracted: 5-Jan-2012. * Travel related outside of Canada.

21


3.0 WILDLIFE SURVEILLANCE 3.1

West Nile Virus

3.1.1 Highlights As stated in Hamilton’s 2009 Vector Borne Disease annual report, 2009 marked the end of funding for viral testing for West Nile Virus in dead wild corvids. Hamilton continued with dead bird sighting monitoring in 2009 however it was discontinued in 2010. Since the beginning of the West Nile virus program dead bird testing was used in conjunction with dead bird sightings as a seasonal “marker” of WNV activity in an area. However, in some health units and in some years, testing was stopped after a set number of positive results were obtained so a comparable picture of positives for an area was never determined. In short, it was difficult to judge risk by bird WNV testing data alone, or to make comparisons from one health unit to another or over time.

3.1.2 Methods In addition, although dead bird sighting patterns have proven to be both temporally and spatially sensitive in detecting WNV activity, it did have its limitations. Sampling was not consistent between health units, as some collected data on all birds while others collected only corvidae and the degree of program promotion has varied across health units. Given the inconsistency for receiving the dead bird sightings, the City of Hamilton ceased mapping dead bird sightings at the start of the 2010 season and discontinued tracking any dead bird sightings reports received from the public. If the public did call to report a dead bird sighting the information was referred to the Canadian Cooperative Wildlife Health Centre (CCWHC) or the caller was provided with the CCWHC’s contact information.

3.1.3 Results, Trends and Comparisons Dead bird testing is no longer required by the Ministry of Health and Long-Term Care as an early indicator of West Nile Virus in Ontario because information collected over the past few years across the province has confirmed when and where the virus will most likely appear. The CCWHC still invites the public or any agency to submit dead birds for possible WNV testing or other examination, potentially with costs attached if submitted by a health unit. In March, 2011, Hamilton PHS did collect and submit a dead falcon at the request of the CCWHC. All other calls from the public reporting a dead bird 22


sighting were referred to the CCWHC or the caller was provided with the CCWHC’s direct line. Hamilton had no reports of positive dead birds from any testing performed by the CCWHC from any submissions of dead birds from the public or other agencies.

3.2

Lyme Disease

3.2.1 Highlights There have been no established black-legged tick populations in Hamilton to date; therefore pre-established triggers set by the MOHLTC have not been met for active Lyme disease surveillance. Small mammal collection would be the second phase of an active surveillance program.

3.2.2 Methods The methods for small mammal surveillance should meet the guidelines set out by in house policies and procedures adopted from Methods for Trapping & Sampling Small Mammals for Virologic Testing, CDC September 1995.

3.2.3 Results, Trends and Comparisons At this time, there is no data available to compare.

3.3

Other Vector Borne Diseases

3.3.1 Highlights At this time there are no wildlife surveillance programs for the four reportable vector borne diseases outlined in Regulation 559/91 under the Health Protection and Promotion Act that include malaria, plague, tularemia, and yellow fever. Eastern Equine Encephalitis (another VBD not listed specifically as a Reportable disease in the Regulation) also did not require any wildlife surveillance in 2011.

3.3.2 Methods Not applicable.

3.3.3 Results, Trends and Comparisons Not applicable. 23


4.0 VECTOR SURVEILLANCE 4.1

West Nile Virus

4.1.1 Adult Mosquito Surveillance Highlights Since 2001, Hamilton Public Health Services has been collecting, identifying and testing adult mosquitoes for WNV activity throughout Hamilton. The number of adult mosquito traps set weekly has increased from four in 2001 to 42 in 2011. These 42 trap locations are depicted in Figure 4. This map also shows traps in relation to the mosquito breeding habitat types, the other land classifications and the 2011 public land standing water sites that were treated by the City of Hamilton. These habitat types and land classifications are available in Appendix B. Adult mosquito surveillance systems have expanded over the years and currently allow for tracking of adult mosquito densities, species, and infection rates over time and space. Most mosquito species are active at sunrise and sunset due to low winds, moderate temperatures and high humidity. During the day, most mosquitoes rest in dense vegetation, culverts and catch basins but may be active throughout the day in areas with sufficient shade. Females require the blood meal to obtain the necessary protein for egg development and will feed on a broad range of hosts including both birds and mammals (including humans). For the mosquito populations across Hamilton, Cosray Labs, the mosquito identification and viral testing contractors, also noted in their report that, “Special consideration should be given to Oc. japonicus, a highly competent WNV vector species first discovered in Ontario in 2001. Since then this species has been found in larger numbers and over a wider range in Southern Ontario. Since the numbers of identified Oc. japonicus were higher this summer at 559 specimens (compare to 392 in 2010), its ability to expand is worth monitoring.� Large numbers of this species were caught in the early weeks of September, following the peak of the Culex population at the end of August. The concern for Oc. japonicus is that it is a relatively new species for Ontario and can transmit WNV.

24


Figure 4: Mosquito Natural Habitats and other land classifications overlaid with 2011 Mosquito Traps and Treated Mosquito Breeding Areas* * The treated mosquito breeding areas, also known as water sites, were treated in 2011 by Pestalto Environmental Health Services based on a high threshold finding of >31 larvae during dipping. Sites that had larvae below the threshold amount were not referred to Pestalto for further treatment.

Of particular interest was the novel use of the habitat information in conjunction with the season-to-date patterns in mosquito data to predict which further traps would capture positive mosquitoes in the season. These results were used in combination with other risk information to target control efforts. Out of the total 15 traps identified as likely to capture positives during the season, 67% (10 traps) were positive during the 2011 WNV season. Methods Accumulated Degree Days (ADD) information was received and reviewed through the season. This measurement is positively associated with the viral load in an infected mosquito and thus the increased risk of transmission of WNV to humans. A degree day is a unit of measurement of degrees of temperature 25


above a fixed reference temperature for one day (24 hours). ADDs are the continuous addition of consecutive degree days from a set starting point. For example, the temperature for Cx pipiens/restuans has been set at 18.3 C. If the average temperature on the first day of the season was at 20.3 C and 21.3 on the next day then two degree days would be accumulated the first day and 3 degree days the second day, giving a total of 5 ADDs. The number of adult mosquito traps set each season has varied. From 2001 to 2011 the numbers of traps set each year were: 4, 10, 14, 43, 41, 35, 43, 41, 43, 42, and 42, respectively. For the purpose of year-to-year comparisons of trends in mosquito abundance, analyses for each vector species used the median pertrap count in the 9 traps that have been consistently located since 2002. They are Trap A1, B1, C1, D1, G1, J1, K1, L1, and M1. Table 3 lists the 2011 adult mosquito trap locations throughout the City of Hamilton. To maintain a level of confidentiality for trap sites on private properties, the locations are based on generalized areas such as the former political boundaries that existed prior to the amalgamation of Hamilton in 2000, or by general defining geographic boundaries (e.g. areas within lower Hamilton or on the “Mountain�). In 2011, 42 traps were set on a weekly basis commencing at Week 24, with the exception of weeks 40 and 41. During these weeks, the number of traps was reduced to 29 for staff efficiencies and because the mosquito season was moving into diapause with an expected decrease in risk. The 29 trap locations plus Ancaster’s will be the main traps set for the 2011 season to continue with efficiencies to the program (reduced staff time and lower expected mosquito identification and viral testing costs).

26


Table 3: City Of Hamilton Adult Mosquito Trap Locations 2011 Areas Trap Locations by General Area

Trap Code for traps viral tested

1 2 3

Ancaster Dundas Flamborough

4 5 6

Glanbrook East Mountain Central Mountain West Mountain Lower Central Hamilton Lower East Hamilton Lower West Hamilton Lower Stoney Creek Upper Stoney Creek Total

12 C1, L1, 26, 38 D1, 21, 22, 48, 49 13, 52, 56 11**,16 K1, S1, 41**

7 8 9 10 11 12

# Traps per Area Viral Tested 1 4 5

Trap Code per Area not Viral Tested

Total Number of Traps per Area 1 4 5

3 2 3

3 2 3

B1**, 25, 45 J1, M1**, 17, 30 15, 34, 47**, 57, 58 44, 54*, MAC

3 4

3 4

5

5

2

2

A1**, G1, 14, 29 51, 55

4 2

A3, A4, A5, 8 A6 2

38

4

42 Traps

Red traps are the 29 traps set for the last two weeks of the 2011 season plus the Ancaster traps. These 30 traps are expected to be the only traps set in 2011. *Trap 54 was decommissioned due to poor access and historical low mosquito yield. Trap “MAC” was added in Week 31 to replace 54. **Bolded traps have had repeat positive pools in at least one season AND positive pools across multiple seasons from 2002 to 2011

Centers for Disease Control (CDC) light traps are used to capture adult mosquitoes using carbon dioxide and light to attract host-seeking adult female mosquitoes. As part of the adult surveillance activities, Cosray Labs identifies and tests three pools of WNV vector species, as per the MOHLTC directive. These pools are homogenized, extracted and viral tested using the “gold standard” real time RT-PCR criteria. Vectors of EEE (or ‘triple E’) were also evaluated weekly and tested as per MOHLTC recommendations.

27


Adult mosquito West Nile virus infection rate (pooled) was calculated by biascorrected maximum likelihood estimate for point estimation (MLE) using the software package “PooledInfRate v. 4.0” provided by the US Centers for Disease Control and Prevention (http://www.cdc.gov/ncidod/dvbid/westnile/software.htm). New to the VBD program was the use of the habitat information in conjunction with the season-to-date patterns in mosquito data to predict which further traps would capture positive mosquitoes in the season and then to further assess the importance of each area represented by these traps in WNV transmission to humans. This analysis was conducted once the first adult mosquito traps tested positive, in the first week of August. Since the initial positive traps appeared visually to be generally located around the escarpment area, the escarpment was hypothesized to be a key influence to finding positive mosquitoes in the traps. In order to explore the potential association between habitat type and the mosquito viral testing results, the habitat that a given trap represents was measured by defining a “trap buffer zone” as a 1200 meter distance from the central point of each trap, and then the underlying habitat types for each trap were identified using the GIS habitat layer (detailed in Appendix C). The percentage of land area comprised by each habitat type within this buffer zone was then calculated for each trap. This “trap habitat” was used in the prediction analyses and also displayed in the geographically-based interactive risk assessment tool, Google Keyhole Markup Language, as an attribute for each trap in a pie chart format. The habitat composition for the traps that had WNV positive mosquitoes were visually compared to traps without any WNV positive mosquitoes using an interactive table format. The three habitat types with the largest proportion representation within the positive traps “trap buffer zones” (excluding catch basin habitat) were further analysed using risk ratios (where exposure = “any proportion given habitat type” / “no proportion” and outcome = adult mosquito testing result WNV positive: “yes” / “no”). The habitat types with statistically significant risk were used to create a list of “predicted WNV areas” for the season. Within the “predicted WNV area” list, priority was assigned based on season-todate burden of each vector species with at least one WNV positive pool, with more weight given to the more competent vector species Cx. pipiens/restuans and Oc. japonicus. This priority was then refined by distance to an existing positive trap and population density. Results, Trends, and Comparisons According to Cosray’s 2011 report to Hamilton “The Accumulated Degree Days (ADD) observed in the City of Hamilton this summer closely follows that of 2010 and of 2007 (a year with 3 WNV-positive mosquito pools) , except the month of 28


July where the temperatures were higher.” Of note is the mosquito abundance patterns seen this summer. Cosary Labs reported that the “City of Hamilton experienced moderate rainfall in June and only 12.1 mm during July, thus affecting the populations of Ae. vexans and Oc. trivittatus.” In 2011, the most abundant mosquito vectors were identified as the floodwater mosquito, Ae. vexans, and the container species Cx. pipiens/restuans. The number of Culex species identified increased from 3,800 in 2010 to just over 4,400 in 2011; while the number of Ae. vexans identified decreased by half of what was identified in 2010. Additionally, this season found lower numbers of Oc. trivittatus species, as only 3,312 specimens were identified in 2011 compared to 10,023 in 2010. According to Cosray Labs, approximately two hundred female mosquitoes were identified per trap and tested for three pools of WNV vector species. Table 4 details the vector species abundance totals for the City Of Hamilton. Table 4: Vector Species Abundance Totals in the City of Hamilton, 2011 WNV Vector Species (Listed by MOHLTC WNV-Testing Order of Preference) Cx. pipiens/restuans* Cx. salinarius Oc. japonicus Cx. tarsalis Oc. triseriatus An. punctipennis Oc. Trivittatus* An. walkeri Oc. Stimulans* An. quadrimaculatus Total WNV Vectors * Top three are in pink

Number of Female Specimens Identified 4403 30 559 0 277 463 3312 46 1315 481

% of Total Vectors Identified 40.4% 0.3% 5.1% 0% 2.5% 4.3% 30.4% 0.4% 12.1% 4.4%

10886

100%

Figures 5 and 6 show the trend in the abundance of adult mosquito vectors from 2003 to 2011; the primary vector species Culex pipiens/restuans in the former chart and the three species that were positive for the first time in Hamilton during the 2011 season in the latter chart. These species are displayed in separate charts because of the large difference in weekly count between Culex sp (maximum weekly count 43) and the other vector species (maximum weekly count 5). The median count of the Culex species dropped dramatically after the inception of the catch basin treatment program in 2003, and was comparatively low across the 2011 season. The median counts of Ochlerotatus triseriatus and Anopheles quadrimaculatus were very low except in 2005; and Ochlerotatus japonicus has been increasing since 2006.

29


Weekly median number of adult Culex pipiens/restuans per trap City of Hamilton, 2003 to 2011 mosquito seasons. 45 Start of vector control program

Median number of mosquitoes per trap

40 35 30 25 20 15 10 5 0 2003

2004

2005

2006

2007

2008

2009

2010

2011

Trap Week (mosquito season = week 20 to 44) Note: M edian is based on counts from 9 adult mosquito traps that have had a consistent location over all 9 seasons. Source: West Nile Virus M aster Database, City of Hamilton. Extracted: 2011-12-05.

Figure 5: Weekly median number of Culex pipien/restuans mosquitoes per trap

Median number of mosquitoes per trap

Weekly median number of adult mosquitoes per trap by selected WNV vector species, City of Hamilton, 2003 to 2011 mosquito seasons. Oc Triseriatus 5

Oc Japonicus An Quadrimaculatus

4 3 2 1 0 2003

2004

2005

2006

2007

2008

2009

2010

2011

Trap Year and Month Note: Median is based on counts from 9 adult mosquito traps that have had a consistent location over all 9 seasons. Source: West Nile Virus Master Database, City of Hamilton. Extracted: 2011-12-07.

Figure 6: Weekly median number of mosquitoes per trap Throughout the 2011 season, 733 viral tests were completed for 42 trap locations with 31 pools testing positive for WNV from 18 of the 42. As mentioned, three West Nile Virus vector species were positive in Hamilton for the first time in 2011

30


since trapping began in 2001. These included Anopheles quadrimaculatus, Ochlerotatus triseriatus and Ochlerotatus japonicus species. Table 5 indicates positive trap results in order by trap location. Table 6 presents the trap results in order by trap week. Both tables include specimen counts and mosquito collection dates. The trend in Culex spp. infectivity rate from 2002 to 2011 is illustrated in Figure 1 (page 8). The WNV infectivity rate among adult Culex mosquitoes in 2011 was the second highest measured since the program inception.

31


Table 5: 2011 Hamilton Positive Traps - By Trap Location Trap Code

Week 31

Week 32

Week 33

Aug 3

Aug 10

Aug

16

Week 34

Week 35

Week 36

Week 37

Week 38

Aug 23

Aug 30

Sept 7

Sept 13

Sept 20

(started Tuesday collection)

13

1 pool

1 pool

(1 An quad)

(5 Cx)

Total Pools per trap

(Wed b/c of Labour Day)

2

1 pool

14

1

(10 Cx)

1 pool (3 Cx)

15

1

1 pool

29

1

(3 Cx)

1 pool

1

pool

(40 Cx)

(22 Cx)

30

2 pools (40 and Cx)

Cx 40

4

1 pool

34

1

(5 Cx.)

1 pool (1 quad)

41

An

1

1 pool (1 Oc japonicus)

45 47

1 pool

1

(5 Cx)

1

pool

2

(26 Cx)

1 pool (5 Oc japonicus)

52

1

1 pool

55

1

(3 Cx)

1 pool (5 Cx)

56

1 1 pool

B1

1

(1 Cx.)

1 pool G1

(1 Japonicus)

Oc.

1

1 pool

1

(1 Cx.)

(1 oc japonicus)

2 pools

1 pool

(11 Cx. and 1 Oc. triseriatus)

(1 Cx.)

J1 K1

2 pools L1 M1 18 traps 42 positive

( 2 Cx and 10 An. quad)

pool

3

2 pools (1 Cx and 3

4

An quad)

1 pool

1 pool

(32 Cx) 8 pools 6 traps 4 species

(27 Cx) 5 pools 4 traps 2 species

2

1 pool 6 pools 6 traps 2 species

2 pools 2 traps 1 species

3 pools 2 traps 1 species

1 pool 1 trap 1 species

3 pools 3 traps 3 species

3

(6 Cx) 3 pools 3 traps 2 species

31 pools 4 species

32


Table 6: Test results for all thirty-one WNV-positive pools by Trap Week Specimen Trap Mosquito Species Count 47 Cx. pipiens/restuans 5 G1 Oc. japonicus 1 J1 Cx. pipiens/restuans 1 K1 Cx. pipiens/restuans 11 31 K1 Oc.triseriatus 1 L1 Cx. pipiens/restuans 2 L1 An. quadrimaculatus 10 M1 Cx. pipiens/restuans 32 Total Number of Positive Mosquito Pools = Eight (8) 13 An. quadrimaculatus 1 14 Cx. pipiens/restuans 10 32 L1 Cx. pipiens/restuans 1 L1 An. quadrimaculatus 3 M1 Cx. pipiens/restuans 27 Total Number of Positive Mosquito Pools = Five (5) 13 Cx. pipiens/restuans 5 30 Cx. pipiens/restuans 40 34 Cx. pipiens/restuans 5 33 52 Oc. japonicus 5 55 Cx. pipiens/restuans 3 5 Cx. pipiens/restuans 5 Total Number of Positive Mosquito Pools = Six (6) 30 Cx. pipiens/restuans 22 34 B1 Cx. pipiens/restuans 1 Total Number of Positive Mosquito Pools = Two (2) 29 Cx. pipiens/restuans 3 35 30 Cx. pipiens/restuans 40 30 Cx. pipiens/restuans 40 Total Number of Positive Mosquito Pools = Three (3) 36 15 Cx. pipiens/restuans 3 Total Number of Positive Mosquito Pools = One (1) 41 An. quadrimaculatus 1 37 45 Oc. japonicus 1 47 Cx. pipiens/restuans 26 Total Number of Positive Mosquito Pools = Three (3) J1 Oc. japonicus 2 38 K1 Cx. pipiens/restuans 1 M1 Cx. pipiens/restuans 6 Total Number of Positive Mosquito Pools = Three (3) Grand Total = 31 Positive Mosquito Pools Week

Date Specimens Trapped 2011-Aug.-03 2011-Aug.-03 2011-Aug.-03 2011-Aug.-03 2011-Aug.-03 2011-Aug.-03 2011-Aug.-03 2011-Aug.-03 2011-Aug-10 2011-Aug-10 2011-Aug-10 2011-Aug-10 2011-Aug-10 2011-Aug.-16 2011-Aug.-16 2011-Aug.-16 2011-Aug.-16 2011-Aug.-16 2011-Aug.-16 2011-Aug-23 2011-Aug-23 2011-Aug-30 2011-Aug-30 2011-Aug-30 2011-Sept-07 2011-Sept-13 2011-Sept-13 2011-Sept-13 2011-Sept-20 2011-Sept-20 2011-Sept-20

Table 7 outlines the positive trap locations within Hamilton since positive traps were identified from 2002 to 2011. The table lists traps positive only once, traps 33


positive multiple times in a season, or traps positive across multiple seasons. Six traps have had repeat positives in at least one season and positive traps across multiple seasons: A1, B1, M1, 11, 41, and 47. These traps are located in six of the twelve geographic areas that define the city (see Table 3).

A1 B1 C1 D1 F1 G1 J1 K1 L1 M1 S1 11 13 14 15 17 18 19 20 28 29 30 34 38 40 41 44 45 47 48 52 55 56 57

Total

3 4 1 1 1 1

1

1

1

2011

2010

2009

2008

2007

2006

2005

2004

2003

2002

Table 7: Hamilton Positive Traps – 2002-2011* and Predicted Traps 2011

2 1

1

1

1

1

1 2 3 4 3

1

1 2 1

1 2 1 1

1 2 1

1 1 1 1

1 1

1

1 4 1

1

1 3 1

8 5 1 1 1 4 2 3 4 6 1 3 2 1 3 2 2 1 1 1 2 4 4

Positive only once

Repeat positive in one season or more √ √

Positive multiple seasons √ √

√ √ √ √ √ √ √ √

On 2011 Predicted Trap List (+ = WNV positive) Predicted + Predicted Predicted Predicted + Predicted + Predicted + Predicted + Predicted +

√ √ √

√ √ √ √ √ √ √ √ √ √ √

1 2

1 4 1 1 3

1 1 1

1 1 1

√ √ √

1

1

Total positive Pools

√ √

Predicted + Predicted

Predicted + Predicted + Predicted Predicted + Predicted

11

2

8**

2

14

3

4

0

1

31

76** Pools

14 traps positive once

12 traps with repeat positive in same season

11 traps with positives across seasons

15 traps on 2011 predicted list 9 were WNV positive

Lines shaded in pink have trapped multiple positive mosquitoes in a single season and across multiple seasons (total of 6 traps). Lines shaded in grey have not caught WNV positive mosquitoes.

34


*This table does not include all trap sites per season - only those with positive results from all seasons or were on the 2011 predicted trap list (total 34 of 42 traps). Details about when a trap location was started are not included. ** A single trap (10Y) was only used in 2004 for hot spot trapping and had a positive result for a total of 8 positive traps in 2004 and a total of 76 positive pools from 2001 to 2011.

Analyses determined the escarpment habitat type to be the only statistically significant contributor to the trap testing results in 2011 (RR=10.4; 95% CI (1.3229.3)). Based on these results, a list of potential WNV areas (represented by trap location) was generated and ordered in priority for the purpose of targeting control efforts in this season. The first positive trap occurred in week 31 and by week 34, out of the total 15 traps identified as likely to capture positives, 60% (9 traps) were positive ccompared to 22% of the non-identified traps (6 positives out of 27 traps). Over the whole season, 67% of the predicted trap list registered at least one positive result, and 5 traps recorded positives in multiple weeks. See Table 7 for results.

4.1.2 Larval Mosquito Surveillance Highlights Management of mosquito breeding areas and control of larval populations decreases the number of adult vector mosquitoes. Fewer potentially infectious adult mosquitoes in turn reduce the risk of humans being bitten by infected mosquitoes. Almost any natural or artificial container that holds water for a week or more can serve as a mosquito-breeding site. Man-made sources such as storm water catch-basins are one such container type and are found within the urban boundary and in some of the settlement areas. Culex pipiens, the primary mosquito, for both the amplification cycle and the spread of West Nile virus to the human population, has been found in City catch basins as well as other standing water sites. Methods Surveillance for developing mosquito populations began in the City of Hamilton during the 2003 season, and continues to date. There remain three primary components to this surveillance: storm-water catch basin monitoring, routine monitoring of stagnant surface waters on public lands including roadside ditches, and targeted monitoring/ground-truthing in response to complaints. All water sites monitored have been identified through a combination of public complaints, field surveillance and GIS mapping techniques to identify where water has been found to be standing or where it may collect and stand for a period of time (assessed by topography and soil type to predict water accumulation). Once a site is validated through a field visit, it remains active in

35


PHS’ monitoring system until the source is either eliminated or referred to the larviciding contractor for treatment. Seasonal Field and Laboratory technicians (“WNV Techs”) are trained at the beginning of the season to ensure proper sampling and site identification techniques are practiced. Breeding site characterization training includes learning and capturing data on: presence of water, vegetation assessment, temperature, water quality, pool size, and categorization into one of the habitat types. A larval sample consists of a group of one or more dips to a maximum of 10 dips, into the water with a dipper (container to capture the larvae), as per the Ministry of Environment sampling protocol. Each mosquito larval sample is characterized as low (1-6 larvae), moderate (7-30 larvae), or high (>31 larvae). The larviciding contractor conducts treatment and subsequent monitoring/treatment once a referral is made. In 2005, Hamilton began using a low count as the trigger to treat to achieve maximum use of the larviciding contractors’ services, as well as to further control mosquito breeding. However since 2009, a “high threshold” count (greater than 31 larvae) has been used for referrals as a cost recovery measure. When a site presents with larvae, the sample is collected and returned to the City’s WNV laboratory for speciation using the microscope. A contract biologist provides initial larval speciation training and then performs two Quality Assurance visits (QA checks) throughout the season to verify the accuracy of the larvae identified by the seasonal techs. Each QA report indicates the correct species and notes any errors by the techs. In 2011, seasonal staff achieved an accuracy rating of 71% and 82% on site visits conducted in July and August, respectively making an improvement as the season and their related experience progressed. Results, Trends, and Comparisons In 2011, approximately 400 potential vector breeding areas widely distributed across the City of Hamilton were monitored, as shown in Figure 7. Seventy three (73) of these water sites were referred to the larviciding contractor for treatment, identified by a green dot in the map. A small number of sites referred for treatment were excluded from the map as they were not part of the monitoring program.

36


Figure 7: Potential Mosquito Breeding Areas (water sites) Monitored and Treated in 2011 The monitored water sites are characterized using habitat criteria set by GDG Environmental Ltd from a 2005 contracted project. All sites were re-classified into 11 habitat types, which are explained in Section 4.1.1 of this report. Reclassification remains an ongoing exercise which is repeated at each visit, for accuracy. Table 8 lists the habitat sites and the proportion of sites treated in 2011. Table 8: Monitored potential mosquito breeding sites and proportion of sites treated, City of Hamilton, 2011 Habitat Type (10)

Number of Sites

Surveillance Visits

Treatments

Forest

6

74

22

Woodland Pool

10

120

30

Field Pool

12

162

21

Ditch/Outfall

40

526

105

Pond (SWMP etc) 4 Mix (artificial 1 containers etc)

43

8

17

7

Totals

942

193

73

37


4.2

Lyme Disease Surveillance

4.2.1 Highlights Of the 38 ticks submitted for identification by Hamilton residents, three were Ixodes scapularis (black-legged ticks). One additional tick result submitted to the Central Public Health lab is pending. The three known black legged ticks were tested for Lyme disease and all were negative on PCR for Borrelia burdorferi. Two of the ticks were acquired within the province and one was acquired while travelling in New York State.

4.2.2 Methods The VBD program implemented passive surveillance activities that included the submission of ticks received by the public for identification and testing of Borrelia burgdorferi in Ixodes scapularis (black-legged ticks). It should be noted that only those ticks that were difficult to identify or suspected to be Ixodes scapularis were submitted to the Central Public Health Laboratory for identification as per the Ministry of Health and Long-Term Cares’ direction. All others were identified in-house, under a compound microscope using entomology principles. Hamiltons’ Lyme Disease Contingency Plan, developed in 2010, outlines various triggers that would increase PHS’ surveillance activities from passive to active.

4.2.3 Results, Trends, and Comparisons Figure 8 describes the monthly submissions of ticks found on human hosts to Hamilton Public Health Services from 2007 to 2011. As expected, submission of ticks is seasonal with the peak of submissions in May and June of each year with a decrease by August. As the tick surveillance is passive, it is likely that submissions are influenced by public awareness of Lyme disease. It is interesting to note that submissions in 2009 were relatively slight, corresponding to the pandemic influenza time period. Prior to the 2011 season, there were only three ticks submitted to Hamilton Public Health between 2007 and 2010 identified as the vector species and only the 2007 tick from the Freelton area was positive for Lyme disease. The only Hamilton-acquired case of Lyme disease also occurred in 2007. In contrast, 3 of the ticks submitted in the 2011 season were the vector species (with one additional tick awaiting confirmation by the Central Public Health laboratory on

38


species and testing for Borrelia burgdorferi). None of the 2011 vector species ticks were acquired from the Hamilton area.

Monthly submissions of all ticks found on human hosts including the Ixodes scapularis (Lyme disease vector species), City of Hamilton, 2007-2011.

40 35 30 25 20 15 10 5 0

Tick identification and microbial results pending

Ixodes scapularis, indicates single tick

Positive for Lyme disease All 2011 Ixodes scapularis ticks were found in known endemic areas outside of Hamilton .

1 2 3 4 5 6 7 8 9 10 11 12 1 2 3 4 5 6 7 8 9 10 11 12 1 2 3 4 5 6 7 8 9 10 11 12 1 2 3 4 5 6 7 8 9 10 11 12 1 2 3 4 5 6 7 8 9 10 11 12

Number of ticks

Total submissions

2007

2008

2009

2010

2011

Month submitted Source: Ticks Database, City of Hamilton. Extracted: 2011-12-07.

Figure 8: Tick submissions found on human hosts, City of Hamilton, 2007 – 2011

4.3

Other Vector Borne Diseases

4.3.1 Highlights Active surveillance for vectors related to malaria, plague, tularemia, or yellow fever was not undertaken in 2011. In 2011, the MOHLTC requested that health units modify their mosquito surveillance program to incorporate vectors of the Eastern Equine Encephalitis (EEE) virus. This request was due to the recent increase of EEE activity in Ontario and to determine the extent of the virus in the mosquito population.

4.3.2 Methods Vector surveillance for EEE followed the same methods for WNV adult mosquito surveillance. Additionally, the VBD program reviews the mosquito control program at the outset and conclusion of each season (April and October/November) to determine if improvements are required, for example the addition of control sites in rural areas if a mosquito species of concern emerges in rural areas.

39


4.3.3 Results, Trends, Comparisons Of the 616 viral tests completed in 2011, zero pools were positive for the EEE virus. Two specimens (two pools in total in two different trap locations) of Culiseta melanura was collected from Hamilton this year, and tested negative when subjected to Cosray Labs' standardized test for Eastern Equine Encephalitis (EEE).

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5.0 CONTROL MEASURES 5.1 West Nile Virus Control 5.1.1 Highlights The City of Hamilton continues to use an integrated vector management (IVM) model for the control of mosquitoes known to transmit WNV. This means that in addition to larviciding, other prevention strategies including breeding site reduction and enforcement are used. In 2011, Hamilton retained Pestalto Environmental Health Services Inc (“Pestalto for a fourth and final season (based on length of contract) to supply and apply larvicides (as directed by program staff), and to obtain the necessary permits for the application of larvicides to catch basins, private and public lands, in Hamilton. The three pesticides used in 2011 were: methoprene, Bacillus sphaericus and Bacillus thuringiensis var. israelensis (Bti). In compliance with the MOE permit public notification requirements, as per MOE’s document, “Public Notification of a Water Extermination for the Control of Immature Stages of Mosquitoes (Larviciding Programs for WNV)” the larviciding notification ran in the daily newspaper, The Hamilton Spectator, on May 26th, 2011.

5.1.2 Methods In Ontario, the Ministry of the Environment (MOE) is responsible for regulating the application of mosquito larvicides. Permits are obtained by Pestalto prior to the application of larvicides to surface waters or catch basins. The permit numbers for the 2011 were: Catch basins: ƒ #3443-8HCKN7 Surface waters: # 1867-8H8NKY allowed up to 30 treatments totaling up to 100 hectares of surface water with Vectobac 1200L (liquid formulation of Bacillus thuringiensis var. israelensis -B.t.i.). Treatment was permitted to occur between May 26, 2011 to October 31 2011, inclusive.

ƒ

ƒ

# 1867-8H8NKY was issued to include treatment of up to 100 hectares with Vectobac 200G (granular formulation). Treatment was permitted to occur between May 26, 2011 to October 31, 2011 inclusive.

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ƒ

# 1867-8H8NKY was issued to include treatment of up to 100 hectares with Vectolex CG Biological Larvicide (Bacillus Sphaericus). Treatment was permitted to occur between May 26, 2011 and October 31, 2011 inclusive.

Pre-treatment studies of catch basins begins each season with WNV staff monitoring selected catch basins in the spring from a pre-set grid pattern of 39 areas. The first round of treatment occurs once larvae are found, based on a general program policy threshold of finding larvae across the city versus in concentrated sections. The permit obtained allowed for up to 41,000 catch basins along city streets to be treated with Altosid pellets (4.25% methoprene) between May 26th and October 31, 2011. Non roadside catch basins were also treated but were included in the permit to use Briquets. The catch basin treatment areas for Hamilton catch basin treatment program is provided in Figure 9.

Figure 9: Catch Basin Treatment Areas (2011)

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Once treatment commenced in 2011, treatment rounds were repeated based on MOEs’ recommendation and label directions for methoprene. Larviciding mainly occurred at approximately 21-day intervals for treatment efficacy. Different coloured paint was used in each round to signify that treatments occurred. The paint colours for the first, three planned rounds were blue, white, and pink. The fourth round, which was added based on local risk factors was orange. Green paint was used for the special re-treatment project that occurred throughout the summer to indicate which catch basins were retreated after cleanout. Red was used for any roadside or off roadside catch basins treated with Briquets. In 2011, Bti was applied for surface water treatments approximately every seven days, with the exception of a few sites that required fewer treatments based on whether larvae were present. A specific area, Bow Valley, was treated with Bacillus sphaericus from the onset of season. Hamilton PHS maintained a current surface water site inventory that identified new sites through the following information sources: ƒ

ƒ

ƒ

ƒ

Existing municipal records – Hamiltons’ Public Works Department provided a list of known storm water management ponds (SWMP) and updated the list as needed. GIS data – digital elevation modeling (DEM) data allowed for maps to be generated that provided hundreds of potential surface sites to be verified and assessed through field checks. Public complaints –The public was invited to report concerns regarding standing water on public and private lands. Only City owned public lands were treated by the City of Hamilton. Field surveillance - where staff observed new sites while visiting others nearby.

Public surface water sites were monitored for mosquito larvae routinely and included descriptive data (dimensions of site, vegetation, temperature of water). The MOE document Permit Applicant Guide for Municipalities and Health Units: Controlling Mosquito Larvae for Prevention and/or Control of West Nile Virus provided the larval surveillance protocol used by WNV staff to assess surface water sites for WNV. In early spring, seasonal WNV staff was trained to properly assess and define the various water sites into the appropriate City of Hamilton habitat classifications: field pools, ditches/outfalls forests, marsh, mixed (artificial), cattail marshes, ponds, sewage lagoons, woodland pools and creeks/streams/rivers. Staff then utilized Global Positioning System (GPS) units to locate the standing water sites. GPS units provide several advantages to the program including accurate referral of sites to Pestalto for treatment, enhanced mapping ability, and quality assurance checks with respect to managing surveillance data.

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If mosquito larvae were observed at a water site, dip counts were recorded and if the high threshold was met (> 31 larvae) the site was then referred to Pestalto for treatment and subsequent monitoring. Any site that could potentially be remediated was also referred to Public Works. The general public supports the standing water enforcement component of the program by lodging standing water complaints on both public and private lands. The Standing Water By-law 03-173 (officially called, A By-law to Prohibit and Regulate the Accumulation of Standing Water at Specified Times of the Year) is enforced within the urban boundary and settlement areas from April 1st – October 31st each year.

5.1.3 Results, Trends and Comparisons In 2011, three planned rounds of roadside municipal catch basin larviciding were conducted with Altosid Pellets (4.25% methoprene). Re-treatments were also conducted in conjunction with Hamilton Public Works’ special clean out project during the summer (a special project to clean every roadside municipal catch basins in 2011). This clean out contract had to be completed during the summer, therefore PHS, Pestalto and Public Works worked closely together to ensure catch basins were retreated once they were cleaned out. A fourth round was added based on local risk guidelines. Pestalto’s 2011 report to Hamilton, Mosquito Abatement Program for Vector Reduction of West Nile Virus- Final Report for City Of Hamilton Public Health Services states that, “non-roadside catch basins, such as catch basins located within or around home backyards, parks, cemeteries government buildings and long-term care facilities were treated with long lasting briquets. Such catch basins tend to be sparsely and widely distributed. Altosid® Briquets, reputed to have a 120-day residual activity, were used to treat the majority of these catch basins.” Tables 9 outlines the 2011 catch basin treatment dates and product use for all catch basins in the City of Hamilton, and Table 10 specifically outlines the details for non-roadside catch basins. Table 11 provides a comparison of treatment dates from 2006 to 2011.

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Table 9: Roadside and Non-Roadside Catch Basin Treatments, Dates and Product Use for the City of Hamilton in 2011 All Catch Basin Treatments Location

Product

Roadside

Altosid速 Pellets

Non-Roadside

Altosid Pellets

NonRoadside*

Altosid速 XR Briquets

Phase/R ound 1 2 3

Start Date Jun 16 Jul 06 Jul 28

End Date

Quantity

Jun 29 Jul 18 Aug 10

26.52 kg 26.93 kg 27.63 kg

Treatments (# of catch basins) 37,887 38,036 39,081

4

Aug 17

Aug 24

27.47 Kg

39,239

Re-treats

Jul 14

Sept 16

19.82 Kg

28,313

4

Aug 16

Aug 16

7g

10

1

Jun 1605

Jun 16Aug 06

695 Briquets

695

Jun 05

Aug 09

------------

183,261

Overall treatment timeline and total # of catch basins

Table 10: Non-Roadside Catch Basin Treatments, Dates and Product Use for the City of Hamilton in 2011 Non-Roadside Catch Basin Treatments Location Backyard

Start Date June 08

End Date June 08

Treatments 28

Government Building Long-Term Care Park

June 08 June 08 June 08

June 08 June 08 June 08

123 36 508

Parking Lot

Aug. 16

Aug 16

10

August 16

705

Overall treatment timeline June 08 and total # of catch basins

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Table 11: Recent Catch basin Treatments 2006 - 2011 Catch basin Marking* Blue White

Round

2006

2007

2008

2009

2010

2011

1st 2nd

June 8 - 15 July 6 - 13

June 13 - 20 July 11 - 18

June 13 - 25 July 2 - 15

June 22 - July 3 July 13- 23

June16 - 25 July 7 - 20

June 16- 29 Jul 6 - 18

3rd 4th

Aug 3 - 10 Sept 1 - 8

Aug 8- 16 Sept 1- 8

July 23 - Aug 6 Aug 13 - 26

Aug 4 - 13 None planned

July 28 - Aug 9 None planned

Jul 28- Aug 10 Aug 17- 24 (Not planned

Pink Orange

but added because of increased human risk Special Re-treatment project**

Jul 14- Sep16

* Colour Scheme: Dot on catch basin indicates treatment. Colour per round matches same colour scheme in most surrounding health units **Re-treatments conducted in conjunction with the City of Hamilton catch basins being cleaned out during all 4 rounds by Public Works special contract to clean all roadside catch basins in 2011

In 2011, the Customer Contact Centre, a centralized phone line for the residents of Hamilton to report and/or inquire about all programs and services, recorded 98 private and 9 public land complaints. Figure 10 depicts the 2011 WNV public and private standing water complaints. All complaints were investigated by either VBD seasonal staff or public health inspectors within the Vector Borne Disease program.

Figure 10: WNV Public and Private Standing Water Complaints 2011

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Green


Any public standing water complaints requiring control were either referred to Public Works for assessment to permanently remediate; or sites were referred to Pestalto for treatment. The latter would create a permanent water site for ongoing monitoring. Of the 98 private land complaints, three complaints required PHS to issue Orders under the Standing Water By-law, to remove stagnant water. In one instance, an owner did not comply in removing the stagnant water from their pool and subsequently the City Of Hamilton decommissioned the pool, with the associated costs added to their tax bill. In 2011, approximately 400 potential vector breeding areas widely distributed across the City of Hamilton were monitored, as shown in Figure 7. Seventy three (73) of these water sites were referred to the larviciding contractor, Pestalto, for treatment, identified by a green dot in the map. A small number of sites referred for treatment were excluded from the map as they were not part of the monitoring program. Pestalto and PHS staff worked together to improve larviciding control in a localized area (Bow Valley) in 2011 by changing from Bti to Bacillus sphaericus at the onset of the season for a longer lasting residual.

Section 4.1.2 outlines Hamilton PHS’ 2011 larval mosquito surveillance activities. A summary of Pestalto’s treatment and monitoring is presented in Table 12. Table 12: 2011 Pestalto Treatment and Monitoring Summary 2011 Breeding Referred Pestalto 73

5.2

Sites to

Total Number of Surveillance Visits by Pestalto

Total Number Treatments

942

193

of

Total Area Treated (m²)

450,719

Lyme Disease Control

Hamilton has not met any of the triggers to require active tick control in 2011.

5.3

Other Vector Borne Disease Control

In 2011 there were no local no control measures specifically required for EEE, malaria, plague, tularemia, or yellow fever.

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6.0 RISK ASSESSMENT As mandated by Ontario Regulation – O.R. 199/03, “The Control of West Nile Virus”, Hamilton PHS conducts regular risk assessment meetings to discuss the current status of WNV, Lyme disease and other reportable vector-borne diseases in Hamilton. Committee members include: ƒ ƒ ƒ ƒ ƒ ƒ ƒ ƒ ƒ ƒ ƒ ƒ ƒ

Associate Medical Officer of Health (AMOH) Public Health Physician Director , Health Protection Division Manager, Vector Borne Diseases (VBD) Program Manager, Surveillance Unit Manager, Infectious Diseases Program Health Analysts, Surveillance Unit GIS Technologist, GIS Services VBD Specialist, VBD Program Public Health Inspector, VBD Program Public Health Inspector, Infectious Diseases Program Program Secretary, VBD Program (recorder) Epidemiologist (consulted as needed)

In addition to meeting throughout the surveillance season, the Vector Borne Disease staff, Infectious Disease staff, and Surveillance Unit staff meet to discuss the previous season and plan for the next season. Discussions occur formally and informally. Some planning meetings occur via Surveillance Unit West Nile virus planning meetings. In 2011, risk assessment meetings were scheduled from June to October. When a meeting was not held, the VBD Manager or designate sent out summaries to the Associate Medical Officer of Health (or public health physician designate) to confirm the local risk level and to receive any feedback on measures discussed at the meetings. There were a total of nine meetings and eight summaries. Ad hoc meetings were also held with selected members of the committee between regular meetings, as needed. See Table 13 for the 2011 risk assessment meetings and risk level decisions.

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Table 13 Risk Assessment Meetings or Risk Summaries and Risk Level Decisions Data Reviewed

Meeting or Risk Summary Date

Activity

Risk Level Decision

Week 24 Week 25 Week 26 Week 27 Week 28 Week 29 Week 30 Week 31 Week 32 Week 33 Week 34 Week 35 Week 36 Week 37 Week 38 Week 39 Week 40

June 22 (Week 25) June 29 (Week 26) July 6 (Week 27) July 13 (Week 28) July 20 (Week 29) July 27 (Week 30) August 3 (Week 31) August 10 (Week 32) August 17 (Week 33) August 24 (Week 34) August 31 (Week 35) September 7 (Week 36) September 14 (Week 37) September 21 (Week 38) September 28 (Week 39) October 5 (Week 40) October 19 (Week 42)

Risk Summary Risk Summary Risk Summary Meeting Meeting Meeting Risk Summary Meeting Meeting Risk Summary Meeting Risk summary Meeting Meeting Risk Summary Meeting Risk Summary

Low Low Low Low Low Low Low Moderate Moderate Moderate Moderate High High High High High High

The intent of the risk assessment meetings is to present and evaluate all surveillance information to determine the related risk level to the community and to consider possible interventions to lessen the risk where feasible. Risk levels are to be determined for the City of Hamilton and reported to the AMOH. Local Risk Categories The following represents City of Hamilton PHS “Risk Categories”. These were used for the 2011 season as in past seasons. ƒ

No Risk o Off Season –October 15th to March 31st

ƒ

Low Risk o WNV risk will be categorized as low as of April 1st.

ƒ

Moderate Risk st th o Any time between April 1 and October 15 based on risk factors. o The move to moderate risk is intended to communicate an increasing risk of WNV. Because WNV is a seasonal, expected presence in the community, the decision to move to moderate risk would be informed by two or more of the following events: ƒ ƒ

More than 100 ADDs (see Section 4.1.1 for explanation) First WNV-positive mosquito pool

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ƒ

ƒ

Other considerations indicating increasing risk of human WNV infection

High Risk o Any time between April 1st and October 15th o The move to high risk is intended to communicate what is expected to be the year’s period of highest risk of human WNV infection. The decision to move to human risk would be informed by such events as: o Multiple WNV-positive mosquito pools in areas of significant human activity o First human WNV case in Hamilton o Pattern of human cases in adjacent health units o Other considerations indicating peak risk for human WNV infection, including more than 200 ADD s. 1 Note that the high risk level would remain in place until: • the end of the season (October 15th or after) • such time as data indicates a significant drop in mosquito breeding and/or four (4) weeks have passed without additional human WNV cases

A risk level decision is made at the conclusion of each Vector Borne Disease meeting by either the Associate Medical Officer of Health if present, or by the designate (Public Health Physician or VBD Program Manager), with confirmation of the risk level by the AMOH or Public Health Physician following the review of the meeting summary. The specific display of the information is made in response to how the virus is circulating in the community. For example, in past years with the indication of high WNV activity, risk assessment meetings have included surveillance for potential clusters of dead bird sightings, interpolated surface maps for each vector species, infectivity rate among vectors, as well as epidemic curves and point location maps for suspect and confirmed human WNV cases. In 2011, the program and surveillance information presented for West Nile virus and EEE virus for mosquitoes, humans and standing water, and for Lyme disease changed to create program efficiencies. The Surveillance Unit team compiled data and shared data based on the local risk so that until a moderate or high risk level was reached or suspected (positive results before meeting), fewer graphs, charts, and figures were produced while virus activity remained low, with the plan to increase and tailor surveillance data as needed when activity increased. As of Week 31 (July 31 to August 6), when 8 positive adult mosquito pools were identified, the Surveillance Unit team responded with additional 1

The MOHLTC suggests that an increase in WNV activity does not usually happen until there are more than 100 ADDs and human cases do not usually occur until greater than 200 ADDs.

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products to help assess local risk at the subsequent meeting where a moderate risk level was decided. Based on the heightened WNV activity, Hamilton then moved from moderate to high risk on September 8th, 2011 with further outputs by the Surveillance Unit and GIS staff. Additionally in 2011, the geographic display of data was migrated from a static map format to an interactive mapping format. In prior years there was interactive mapping available for control purposes (using preset orthophotography and land parcel attributes), but the existing technology proved too cumbersome to incorporate weekly changing surveillance information. Over the 2011 season, GIS staff and Surveillance Unit staff introduced the use of free open source applications such as Google Earth, Google Charts, Hypertext Markup Language (HTML) and Keyhole Markup Language (KML), making it possible to access the weekly mosquito data and display it in an interactive mapping format. The benefits of this new GIS technology was to save time preparing the data for review by automating the data display process and visualizing many different data attributes in a single interface, while maintaining a consistent output format and views of the data filtered by Surveillance Unit set parameters. The new data display process was automated and ran ‘behind the scenes’ using Software called Features Manipulation Engine, which displays the geographic data (such as the trap locations, parcel layer and habitat layer) and the tabular attribute data (such as weekly vector counts and WNV testing results). The data was displayed in two ways, as a trap location point on the map that alters in size and colour based on weekly surveillance results, and also summarized in a pop-out window when the location point is clicked. The interactive maps could be saved from week to week to allow reviews for each week’s results. See Appendix C for more details on the use of FME and Google Earth. At each risk assessment meeting, program updates are provided in addition to a review of surveillance findings. A basic outline of each meeting follows. Program Updates Manager of Vector Borne Diseases provides information regarding communication, education & outreach and operational details to update committee members. WNV among host species surveillance Death among birds was used in previous seasons as a syndromic indicator of WNV circulating in the host species at the local level. As well, laboratory testing of corvids was used to confirm presence of WNV. These activities did not occur in 2011. WNV/EEE among Adult Vector Mosquitoes Surveillance

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Although the mosquito infectivity rate was deemed to be the gold standard, this estimate was considered too unreliable in both sub-Health Unit geographical area and for week-to-week assessments due to small numbers. Low risk: List of pools positive for WNV/EEE by vector species and trap number and season-to-date positive pool data. Positive pools displayed on interactive map by colour change of trap location point. Expanded risk: Addition of time series chart to assess season-to-date weekly trend in abundance of primary vector species. One-time analyses that used habitat, positive pools, vector abundance, and population at risk information to identify subHamilton areas at higher risk. WNV/EEE among Humans Surveillance Low risk: Table of season-to-date cases by case classification and exposure location (Hamilton, other Ontario, outside Ontario). Verbal reports given of any new human cases and suspect cases with evaluation of potential exposure locations. Expanded risk: Addition of epi-curve if required. Lyme Disease among host species surveillance None Lyme Disease among Vector Tick Surveillance Low risk: Verbal reports of suspect vector species ticks and laboratory results including exposure location. Lyme Disease among Humans Surveillance Low risk: Verbal reports given of any new human cases and suspect cases with evaluation of potential exposure locations. Expanded risk: Addition of epi-curve if required. Neighbouring Jurisdictions A summary of the surveillance information from neighbouring jurisdictions is reviewed in order to place Hamilton in a broader context. . Information in this section included some adjacent health units, some Greater Toronto Area health units, States bordering Ontario, and the MOHLTC/Public Health Ontario Vector report data including the Minimum Infection Rate (MIR) and Accumulated Degree Day information.

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Summary: Risk Statement – Low, Moderate or High local risk. Vector Mosquito Control: A second purpose of the VBD weekly risk assessment meetings is to direct targeted vector control activities, most commonly the identification of mosquito breeding areas for remediation and treatment. The information used to inform this process includes: − table of weekly mosquito abundance data by trap and species − per trap attribute data (e.g. location, empty/invalid trapping event) displayed on interactive map − the relative number of vectors in each trap and the vector species caught in each trap displayed on interactive map − a map of the mosquito habitat areas (see Figure 4) integrated midseason into the interactive map as a static pie chart that describes the local habitat composition surrounding each trap − chart of the trend over time in primary vector species abundance for the given trap displayed on interactive map − land parcel information to describe public and private ownership and ortho-imagery contained within our corporate GIS system displayed on interactive map − treatment information from the contractor Vector Tick Control: Tick and human case Lyme disease surveillance findings that may indicate a need for active tick surveillance and/or subsequent control measures in specified areas of the city.

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7.0 PUBLIC COMMUNICATION Under the mandate of the Ministry of Health and Long Term Care (MOHLTC) the goal of the Hamilton Public Health Services’ WNV/VBD program is to reduce the risk of transmission to humans through the implementation of Public Education/Outreach Activities, Media Communications, and a Comprehensive Surveillance and Control program for WNV, Lyme disease, and any other VBD. In 2011, HPHS’ communication plan incorporated a strategic multi-layered approach that included communication to individuals, networks, organizations and communities through mass media, interpersonal communication and events. A three phase communication plan, available in Appendix D, was developed to determine when and what type of activities would be implemented throughout the season. As risk to human exposure increased, various phases would be implemented. Risk was measured by the presence of positive mosquito pools and positive human cases within a localized geographic area based on local risk guidelines. Phase 1 (low risk) would include activities implemented annually and were not influenced by the presence or absence of WNV activity in the community. These activities included posting current information on the PHS website and through media releases, outdoor bus advertisements, a Seniors Review (magazine) advertisement, and radio advertisements on four local stations, alternating on a weekly basis. Furthermore, staff attended three community events to allow for interpersonal communications with the public. A WNV tip sheet (Appendix E) was created outlining key preventative messages and was provided with existing resources to the public. Phase 2 (moderate risk) would include activities implemented in Phase 1 in addition to others to provide increased community awareness of the presence of WNV activity in the City of Hamilton. Phase 2 was initiated in 2011 based on the presence and extent of the number of mosquito pools found positive with WNV. Additional activities included an extended radio advertisement schedule, advertisements in the five local Community Newspapers, and staff attending a fourth community event. Phase 3 (high risk) would include activities implemented in both Phase 1 and 2 with additional activities that would further increase awareness of the presence of WNV within a localized geographic area. This communication phase was not initiated in 2011 as the high risk level occurred in the latter part of the season (September 8, 2011) when added activities to those already occurring were deemed not to be necessary. Messaging about preventing Lyme disease was also incorporated in the WNV radio and print ads. PHS staff also educated the public at the four community

54


events about what Lyme disease is, transmission and preventative measures. A Lyme disease fact sheet (Appendix F) was created and provided to the public at these community events. A complete list of the 2011 outreach activities in chronological order is provided in Table 14. Table 14: 2011 Chronological Order of Communication CampaignEducation and Outreach Activities WNV/VBD 2011

EDUCATION & OUTREACH ACTIVITIES Vector Borne Disease Program presentation

CAMPAIGN/OUTREACH

Part of the Control and Surveillance activities for the WNV city wide prevention plan. Notification ad in the Hamilton Spectator

West Nile virus technicians and public health inspectors on the Vector Borne Disease team responded to public and private land complaints

Festival booths across city and/or to reach diverse community

Staff attended to provide a forum for knowledge exchange by educating the public: ƒ the risks of exposure to West Nile virus and Lyme Disease through interpersonal communication and resource materials; ƒ the recommended use of mosquito repellent for both ticks and mosquitoes; and ƒ to provide DEET and alternative repellents for festival visitors to use during the festivals. Staff also utilized an evaluation tool to collect the public’s perception and knowledge of ticks and Lyme Disease and to determine if any areas within Hamilton should be flagged as a particular area of concern. At the Binbrook Fair booth visitors were also asked their preference to receive outreach messages, specifically what radio station in Hamilton

July 5, 2011

City of Hamilton Healthy Workplace E-bulletin - June 2011 edition of e-bulletin produced by Public Health Services

The dangers of Ticks and Lyme Disease - City of Hamilton Lyme Disease related workplace webpage .

August, 2011

‘PHS@work’ (Intranet for Public Health Services staff).

Home page for each staff included link to West Nile virus page for awhile and see there is a link to our WNV page

January 25, 2011

April 1-Oct. 31 Standing Water By-law In effect May 26, 2011

June 3 – 5, 2011 Dundas International Buskerfest, July 1 – 4, 2011 It’s Your Festival, Gage Park Aug 26 - 28, 2011 Winona Peach Festival, Stoney Creek Binbrook Fair September 16 – 18, 2011

Presented to School of Geography class, McMaster Course- Community and Public Health- Topic – Epidemiology

Notified the public about the treatment program for the season to treat catch basins and surface waters on City lands (Appendix G)

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August/September

Seniors Review August/September Issue. Serves the Hamilton area and Grimsby/Burlington areas

August/September

New promotional resources: • West Nile virus tip sheet • New Lyme Disease information handout

New handouts. See Appendices E and F.

August 9 to October

Hamilton Bus ads- exterior sides

15 ‘King’ posters displayed on sides of buses across Hamilton

August 16 to September 12

Summer radio campaign. Original plan was extended in response to positive mosquito trap results locally (8 pools in one week of trapping)

AD Content West Nile virus and Lyme disease personal protection and prevention messaging.

Ads ran across local stations owned and operated by Astral, Corus, and on 94.7 fm.

Rationale The messaging includes Lyme disease as DEET is recommended for both mosquitoes and ticks. The stations chosen were based on providing messaging across the three major radio networks in Hamilton (Corus, Astral, and Wave) as well as targeting the older adult as they are most at risk of severe illness from WNV infection. Examples of ad content: Corus 10 second ads (in rotation): 1. Are you off to the sports field tonight? Hamilton Public Health Services reminds you to protect yourself and your family from mosquito bites and West Nile Virus. Use a mosquito repellent.     2. Protect yourself from West Nile Virus. Hamilton Public Health Services reminds you to remove standing water on your property and to use a mosquito repellent to avoid mosquito bites.     3. Protect yourself and your family from mosquito bites and West Nile Virus. Hamilton Public Health Services reminds you to use a mosquito repellent. Visit hamilton dot ca backslash westnile for more information 

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October 4, 2011

Vector Borne Disease Program presentation

Presented to School of Geography class, McMaster Course- Community and Public Health- Topic Epidemiology

October 27, 2011 to October, 2012

Hamilton Community Guide VBD ad

This guide is issued to all residents in Hamilton in late October and is available in all Municipal Service Centres, libraries, recreation centres, museums, and other City locations, all year

August 7, 2011 August 12, 2011 August 19, 2011 August 26, 2011 September 2, 2011 September 9, 2011 September 16, 2011

Seven (7) Media Releases

1. First West Nile Virus Positive Mosquitoes in 2011 2. Additional West Nile Virus Positive Mosquitoes in 2011 3. West Nile Virus Update 4. First confirmed human case of West Nile Virus in Hamilton 5. West Nile Virus Update 6. West Nile Virus Update 7. West Nile Virus Update

In 2011 the potential use of social media was also explored including the use of smart tags on promotional material and whether to launch or utilize any social media tools such as Facebook, Twitter, or other tools. Smart tags were incorporated into the WNV Tips sheet (see Appendix E). Some exploratory discussions also occurred with an open source stakeholder regarding the potential use of locally available data to create third party ‘apps’ for public use. More discussions are planned for 2012.

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8.0 EVALUATION 8.1 Communication West Nile Virus An evaluation tool was created in an effort to determine the publics’ opinion of their preferred media to receive health information; and more specifically their preferred local radio station. In terms of evaluating the WNV communication efforts implemented in 2011, this tool inquired if and how WNV messaging was received throughout the season. This evaluative tool was implemented only at Binbrook Fair, the last community event of the season and is available in Appendix H. PHS staff surveyed 212 individuals over the three day event. Of these, 183 or 86% believed that radio was an effective method to communicate health information. The top five preferred radio stations included 102.9 K-Lite FM, FM 94.7 CHKX, Y108, AM 900 CHML and AM 1150 CKOC. As indicated in Table 14, Hamilton PHS placed WNV radio advertisements in four of the top five preferred stations. The fifth station targets younger listeners and therefore does not fall within the targeted audience for WNV communication. When surveyed if respondents had seen or heard WNV messaging in 2011, 145 or 68% stated they had. TV, radio advertisements and print media were indicated as the most common methods in which people had seen or heard about WNV. This may be due to the increased media attention in 2011 as there was heightened WNV activity in Hamilton and across the province. Lyme Disease PHS used an evaluation tool at all the community events (Appendix I) to determine the publics’ knowledge and awareness level of Lyme disease, the diseases’ connection to ticks, and whether people saw ticks of any kind within the City of Hamilton. The results from the festivals are provided in Table 15.

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Table 15: Tick Evaluation Results, City of Hamilton 2011 Tick Evaluation Results for Summer Festivals, Hamilton 2011

Questions on Tick Evaluation Sheet

1. Have heard of Lyme Disease?

you

2. What causes Lyme Disease?

3. Do you know what a tick looks like? If no, show tick Yes No

Yes

No

Tick

Doesn’t know

Said something other than tick

92

30

69

49

3

73

157

52

104

73

24

214

63

153

108

200 663 79% 836

28 173 21%

176 502 61% 824

37 267 32%

4. Have you seen any ticks in Hamilton this year?

Yesif yes where? Name intersection or place or address?

No

49

31

88

84

108

18

191

14

140

133

41

207

14 55 7%

168 465 57% 811

56 346 43%

58 148 18% 806

172 658 82%

FESTIVAL NAME Dundas International Buskerfest June 3 - 5, 2011 It’s Your Festival July 1 – 4, 2011 Winona Peach Festival Aug 26 – 28, 2011 Binbrook Fair Sept 16 – 18, 2011 Totals Percentages Total responses

Summary results of the three evaluations were: ƒ ƒ ƒ ƒ

79% of those polled have heard of Lyme disease 61% stated Lyme disease is caused by ticks 57% stated they know what a tick looks like 82% said they have not seen ticks in Hamilton

Of those who had seen a tick in the City of Hamilton in 2011, Glanbrook (including Binbrook) and Stoney Creek (including Winona) were areas mentioned most; followed by Dundas. Further evaluations may be done in future to help inform communication messages to the public about Lyme disease and its prevention.

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8.2 Website Analysis and MIEH Program Recommendations Hamilton PHS reviews website content prior to each season to prepare for the season. Changes were made to the website pages in 2011 including ensuring Hamilton’s surveillance were accurate and removing outdated or redundant content. Future plans include reconfiguring the website as part of the City’s larger plan to redesign its pages and functionality. PHS also collaborates with McMaster Institute of Environment and Health (MIEH) and since 2006 they have provided a yearly analysis of the website component of the WNV communication plan. This analysis provides insight into the uptake of the program’s information and helps program staff decide what changes should occur to the webpages. MIEH also informs the program about global issues related to WNV which further informs decision making to provide current and relevant communication as well as support the WNV/VBD surveillance and control efforts. In particular, MIEH reviewed the report by the European Center for Disease Prevention and Control (ECDC) about the 2010 WNV outbreak in Romania and provided advice from it for Hamilton’s program. The website analysis and program recommendations are provided, below. For the full report, see Appendix J. MIEH Website Summary Over the last ten (10) years of the Hamilton program, public interest in both WNV and the activities of the WNV program, continue as evidenced by the parallel of increased website traffic over the designated WNV peak season of May to September. , In recent years, there has been a decrease in the total number of web hits except for 2010 which showed an increase from 2009 (13,362 hits in 2009 to 14,011 in 2010). In 2011 the total hits declined to 6,808. The corporation of the City of Hamilton has an estimated 6,700 web pages for potential viewing so interest in the WNV website should be viewed within this context. When we consider the variety of public health concerns introduced to the population in recent years, for example, HINI, West Nile virus and other vector borne diseases are still of interest to the general public. During the second half of 2011 (August to December) the IT department for Hamilton Public Health Services contracted with a new provider for data retrieval, subsequently, this led to changes in both potential data analysis, as well as the ability to compare data from previous years with the current year. Although data for the total number of ‘hits’ would still be available, entry/exit ‘hit’ data including reviewing targeted webpage data would necessitate a new analysis. Based on scientific evidence May until October is the time of year to conduct surveillance and, as the season progresses, for people to be the most cautious in 60


terms of the potential for WNV infection. During this time period, we consistently found a marked increase in web site ‘traffic’ as reflected in the total number of targeted hits. The ‘targeted’ pages offer advice on: • personal protection, • the city wide surveillance and control program • surveillance results, and • the default ‘home’ page which contains links to content pages and external stakeholders Specific ‘targeted’ pages were reviewed and ranked in popularity from the overall number of hits to the program pages. The home page, program history (‘stats’), and the general question and answer pages were the most popular in 2011. See Tables 16 – 18 for all related results. Table 16: Targeted Web Pages within WNV Website, 2010 & 2011 WEBSITE ADDRESS

Description

PublicHealth/WestNileVirus/index.htm

WNV Home page (default)

2010 4617 (45%) 481 (5%) 530 (5%) 563 (6%) 519 (5%)

2011 2443 (48%) 172 (3%) 226 (5%) 361 (7%) 223 (5%)

PublicHealth/WestNileVirus/ReduceExposure.htm PublicHealth/WestNileVirus/WNV-inHamilton.htm PublicHealth/WestNileVirus/History.htm

Reduce exposure to mosquito bites including personal protection information Prevention plans in Hamilton/reducing the risk to WNV Surveillance statistics

PublicHealth/WestNileVirus/Important-Facts.htm

Transmission /symptoms/City of Hamilton plans for reduction/Malathion

PublicHealth/WestNileVirus/QA-General.htm

Transmission/ Symptoms/Type of mosquito/time of day, etc Outlines information on WNV and children including prevention, protection and treatment options

778 (8%)

418 (8%)

739 (7%)

262 (5%)

Various website links to public health and other agencies involved with WNV includes provincial, national and international links The public can register with PHS to be contacted if when any adulticiding were to occur in Hamilton

491 (5%)

188 (4%)

473 (5%)

156 (3%)

Offers information on the prevention and control of Lyme Disease. As well as guidance for ‘tick’ identification

1031 (10%)

622 (12%)

Total of Targeted pages

10,224

5077

Grand Total of All Hits (Targeted and Non-Targeted)

14,011

6,808

PublicHealth/WestNilevirus/qa-wnv-andchildren.htm PublicHealth/WestNilevirus/links.htm

PublicHealth/WestNilevirus/adultmosquitoregistr y.htm PublicHealth/WestNilevirus/lymedisease.htm

Pink entries were the top three popular pages apart from the home page.

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Table 17: Number of Targeted Hits by Month in 2010-2011 MONTH

January February March April May June July August September October November December Total

Percentage and Number of Targeted Hits WNV 2010 7% 698 5% 542 7% 704 6% 648 8% 821 17% 1738 12% 1269 7% 699 6% 596 5% 528 14% 1400 6% 581

Percentage and Number of Targeted Hits WNV 2011 13% 672 11% 538 10% 495 6% 328 8% 400 12% 591 12% 610 15% 765 7% 368 3% 132 2% 100 2% 78

10224

5077

Table 18: Annual Top Three Targeted Hamilton WNV Pages, 2009 to 2011 1 2 3

2009 General Q/A WNV and Child WNV in Hamilton

2010 Lyme Disease General Q/A WNV and Child

2011 Lyme Disease General Q/A History (Stats)

Despite the general decline in website hits, there appears to be continuing public concern with regards to WNV Prevention/Protection and other vector borne diseases as website traffic has continued. Lyme disease specifically has garnered interest as it has been one of the most popular pages visited within the Vector Borne Disease program. Lyme disease is included in the overall vector borne diseases program. The information page on Lyme disease offers background information, identification (of ticks), prevention, and treatment information on the disease. Activity on the web page indicates an active interest as the site accounted for 10% of total hits for the VBD program to targeted pages in 2010 and an increase to 12% of targeted pages in 2011. The researchers suggest program staff continue to track website activity to this page as an indicator of the public interest in a new and emerging disease of concern.

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The website also provides information on Hamilton’s adult mosquito registry. The registry was first posted to the Public Health website in late July 2009 to provide an avenue for members of the public to learn about the registry. They can contact the WNV/VBD program to add their personal contact information to the registry. If it was determined that adulticiding (adult mosquito control through aerial application of Malathion) were necessary to control the spread of WNV, Hamilton Public Health Services would be committed to notifying residents in the affected areas and to those on the registry a minimum of forty eight (48) hours in advance of the application. Adulticiding has not been performed to date. See Table 19 for hits to the registry from 2009 to 2011. Table 19: Adult Mosquito Public Registry Website Hits 2009 - 2011 Adult Mosquito Registry Hits Web site Activity 2009 January N/A February N/A March N/A April N/A May N/A June N/A July N/A August 31 September 43 October 28 November 13 December 42 Total Percentage of all hits to targeted WNV 157 pages (2%)

Hits 2010 32 22 33 31 48 102 44 29 23 28 56 25 473 (5%)

Hits 2011 26 25 14 8 6 21 24 13 8 4 3 4 156 (3%)

ECDC Report on 2010 Romanian WNV Outbreak In 2011, the European Center for Disease Prevention and Control (ECDC) released their first Mission report on WNV surveillance in Europe. A number of outbreaks in 2010 had occurred after a lengthy period of dormancy (with only sporadic cases reported) which became the catalyst for a review and reassessment of the current ‘risk’ potential and subsequent response in terms of WNV for the European organization. The most severe outbreak occurred in Romania but there were also outbreaks in Greece, Russia, amongst others during 2010. The impetus for the report was a re-assessment of the potential risk of the disease in the light of the series of outbreaks. The Romanian outbreak was notable both for the number of human cases reported and that it occurred after the country had experienced a decade long period of dormancy. In 2010, there was a change in the epidemiological situation and by October 13, 2010 there were 47 confirmed cases of WNV infections (included two deaths). The reporting period included July to September, 2010. More importantly, for the first

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time in more than ten years, the geographic locations of reported cases included counties in the central and northern part of the country. The variables implicated in fatalities/infections included age (60+) and gender (higher incidence between males than females). During the epidemiological investigation, all confirmed cases were interviewed for the occurrence of a series of potential risk factors for WNV infection. Of these, 87% reported mosquito bites, 30% reported stagnant water around their residence, 21% reported gardening as a leisure activity, and 30% reported rearing poultry. Entomological surveys were carried out collecting mainly resting mosquitoes with different types of aspirators and some active mosquitoes with different type of traps. Of the 3,689 mosquitoes collected, 94–96% were Culex pipiens, and one pool of Cx. pipiens resulted in WNV antigen positivity. The ECDC/WHO team found similarities between the 2010 Romanian outbreak and a 2010 outbreak in Greece, both outbreaks showed the peak of the outbreak towards the end of August, eventually tailing off in September. This suggests that the conditions in 2010 were equally favourable to the circulation of WNV in Greece and Romania. It is unconfirmed whether these conditions were due to climatic factors (rainfall, temperature, humidity, etc.), the lineage of virus introduced, bird migration, mosquito vectors involved, etc. Overall, the report states it may be one or more of these variables. Since the goal of the mission report compiled by the ECDC/WHO was to develop a risk assessment not just for Romania but also the rest of Europe, they conclude, ‘considering the outbreak in both Greece and Romania in the same year, it is clear that ecological parameters in parts of Europe are currently favourable for viral activity. Furthermore, support for this assumption comes from reports of human outbreaks, which occurred during the same time period in Russia and Hungary, and equine outbreaks in Morocco. “Thus, the need for strengthened surveillance as well as preparedness plans that cover all aspects involved in the transmission of this disease, including human surveillance, entomological surveillance, veterinary surveillance (including birds and horses), and blood and tissue safety are recommended.” The Local Connection MIEH has partnered with the Hamilton VBD (formerly the West Nile Virus) program for the past six (6) years and is familiar with the program surveillance/outreach activities and reported statistics. Since the inception of the program the source reduction and prevention component of the program has met with apparent success, with fewer human cases occurring once larviciding and other controls occurred. Thus, we believe the information gathered by ECDC/WHO in their mission report regarding the Romanian outbreak, could benefit the Hamilton PHS Program Manager in terms of both on-going and future planning of the Hamilton V.B.D. program.

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In particular, the primary lesson may be the importance of continued vigilance considering the severity of the Romanian outbreak, which was preceded by a ten (10) year period of dormancy. The goal of the Hamilton program is to minimize the impact of WNV through district-wide surveillance that directs integrated vector management based mosquito control activities at a level commensurate with the risk of human illness. This means an emphasis on surveillance, public education, and source reduction. Surveillance includes collecting and identifying sample pools of mosquitoes, again, referring back to the Romanian report, this activity was essential during the outbreak for identification and tracking purposes. Unlike Romania, these activities are currently mandatory and guided by the Ontario Ministry of Health and Long Term Care (MOHLTC). As stated earlier in this report, in 2011 the local Hamilton program saw not only a notable increase in the number of ‘total positive mosquito pools’ as of August but experienced its highest number of confirmed human cases since 2006. All of the risk factors (mosquito bites, stagnant water near residences, leisure gardening, and rearing poulty) identified during the Romanian epidemiological investigation, except rearing poultry, have been the focus of the education and outreach component of Hamilton’s program. MIEH Conclusion Program outreach by Hamilton PHS traditionally has two primary message streams, the first being educating and identifying risk activities and secondly, advocating individual protection measures, including applying insecticide, awareness of dusk till dawn vulnerability and wearing protective clothing while participating in outdoor activities (the program also implements population level protective measures, eg. larvaciding). Hamilton also helps to reduce mosquito development through the enforcement of the Standing Water By-law, which takes effect from April 1 to October 31 each year, the time period, which encompasses WNV season. The reporting period for the Romanian outbreak included July 4 till September 13, 2010 with the majority of cases reported in the month of August (65%). Although the Hamilton program is active throughout the year, as previously stated the major focus of WNV activities occurs from May to September. Thus, it would appear to be prudent for the Hamilton PHS program to not only continue its prevention and surveillance activities at the local level but also its education and outreach activities. Continuing to raise awareness among the Hamilton public and building on the public interest evidenced by the website traffic activity will enable the program to draw upon that knowledge should the epidemiological conditions found in Europe in 2010 duplicate themselves locally. In addition, MIEH recommends that Hamilton Public Health Services continue to collaborate with MIEH for the analysis of website ‘traffic’ activity in order to monitor ongoing ‘consumer need’ for information. MIEH also recommends that PHS maintains current public awareness levels and remains vigilant in the event 65


of potential epidemiological changes in WNV, and subsequently, to prioritize the distribution of program resources including Web site design and development and other outreach/educational activities.

8.3 Program Evaluation In 2011 the West Nile virus component of the VBD program was audited by City of Hamilton Audit Services and the outcome was for the program to complete outstanding policies and procedures and to conduct a program evaluation within 12 to 18 months of the audit period. This work began in 2011 and will be completed in 2012. Program evaluation is one of the important components of Best Practice Management (BMP) as part of an overall Integrated Vector Management Plan (IVM). However, as stated in the 2010 MOHLTC West Nile Virus Preparedness and Prevention Plan, “measuring the local effectiveness of a health unit’s program is difficult because vector borne disease programs often contain measures that are hard to quantify” Hamilton’s program evaluation will strive to create indicators the program can measure and evaluate season to season by first establishing an evaluation framework.

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9.0 PROGRAM COSTS Communication Costs The 2011 awareness campaign cost approximately $31,000 and included radio and print advertising. This was an increase from 2010 as additional radio advertising was added as part of an enhanced campaign following multiple positive mosquito pools from four mosquito species in week 31. The original communication budget was $15,050. Staffing costs for presentations or participation in outreach were not included in this amount. Actual costs for the overall VBD program, including staff time (salary and wages) are submitted to the MOHLTC through routine reporting. Adult Mosquito Costs The adult mosquito surveillance program involved staffing, training, mileage, and related equipment costs for permanent and seasonal Public Health staff that performed adult mosquito trapping and submission, and other related activities. These associated costs are submitted to the MOHLTC through routine reporting. The cost for adult mosquito surveillance identification and viral testing by Cosray Labs was $42,332. Larval Mosquito Costs The cost of the larval mosquito control program includes both PHS’ staff time, to monitor standing water sites and identify larvae as well as the treatment costs by the larviciding contractor, Pestalto Environmental Health Services. Costs relating to staff time are submitted to the MOHLTC through routine reporting. Larviciding treatments cost were $217,588 in 2011. This included $19,989 to retreat 28,313 catch basins. As outlined in the report, this was completed in conjunction with Public Works’ special clean out project during the summer. PHS, Pestalto and Public Works worked closely together to ensure that catch basins were retreated soon after they were cleaned out. Larviciding began in the City of Hamilton in 2003. See Table 20 for a comparison of costs per season, to date.

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Table 20: Comparison of Treatment Costs, 2003-2011 Year

Cost

Contractor

$516,120

Number of Catch Basin Rounds and Surface Area Treated Three Rounds & 14 Surface Waters sites treated Four rounds & > 100 ha.Surface Waters

2003

$~550,000

2004 2005

$283,540

Four rounds & > 62 ha.Surface Waters

CCMM

2006

$308,929

Four rounds & > 68 ha. Surface Waters

CCMM

2007

$287,213

Four rounds & <5 ha. Surface Waters

CCMM

2008

$176,652

Four rounds & ~6 ha. Surface Waters

Pestalto

2009

$147,458

Three rounds & >65 ha. Surface Waters

Pestalto

2010

$181,477

Three rounds & >115 ha. Surface Waters

Pestalto

2011

$217,588*

Four rounds and special re-treatments throughout season following a Public Works catch basin clean out program & >45 ha. Surface Waters

Pestalto

Orkin PCO GDG

* includes $19989 for re-treatment costs

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10.0 CONCLUSION In 2011 WNV activity increased locally and provincially. There were 31 positive adult mosquito pools and two human cases for Hamilton; Ontario reported 279 positive adult mosquito pools and 71 human cases. For Hamilton, the increased activity in positive mosquitoes triggered an increase in mosquito control and communication outreach in order to prevent potential disease transmission and to help reduce local risk. Increased efforts included adding a fourth round of larviciding of city catch basins and extending the WNV radio campaign further into August and September to share personal protection messages with the community. A fourth community event, the Binbrook Fair, was also attended in October to share protection messages. These activities were part of Hamiltonâ&#x20AC;&#x2122;s Best Management Practices within the Integrated Vector Management (IVM) program. The 2011 season was also a time to consider reviewing the program and two options were to put forward: to perform a situational assessment or conduct a program evaluation. The program evaluation was chosen as the tool to evaluate the program as it was a recommendation from the internal audit. The West Nile virus component of the Infectious Disease program audit recommended that outstanding policies & procedures be completed and that an updated program evaluation be conducted. The program evaluation process began in 2011 and will be finished in 2012. The evaluation report is expected to help shape the 2012 and 2013 program activities including setting up a framework for future evaluations. In order to create efficiencies in the program, at the outset of the 2011 season, the Surveillance Unit team changed how they would compile and present data at the regular risk assessment meetings. Data was compiled and shared based on the local risk so that fewer graphs, charts, and figures were produced while WNV activity remained low with the plan to increase and tailor surveillance data as needed when activity increased. As of Week 31 when 8 positive adult mosquito pools were identified, the Surveillance Unit team responded with additional products to help assess local risk. For the 2011 season, GIS staff also incorporated a new method to display the adult mosquito trap data versus static pie charts of each trap on a map. Through the joint purchase by Surveillance Unit and the West Nile virus program (Vector Borne Diseases program) of a Features Manipulation Engine license, GIS staff were able to present the mosquito trap data using Google Earth. This new method allowed mosquito trap data and habitat information to be presented on the map (on the map directly or in pop up format) per trap location. Although the 2011 saw increased viral activity, in Hamilton and across Ontario, it remains a challenge to predict future seasons. Theories for increased viral activity include mild winters preceding a wet spring or bird populations may 69


fluctuate impacting the reservoir for the virus. Hamilton PHS recommends health units continue to maintain a comprehensive mosquito monitoring, control, and education program to be prepared for changes in WNV or other mosquito borne disease activity year to year. For Lyme disease surveillance, Hamilton did not confirm any evidence of local activity in ticks or people although acquiring Lyme disease within Ontario remains an ongoing threat. In the spring of 2012 the VBD staff will participate in a training exercise to practice field surveillance in a known endemic area of Ontario. The focus of the 2012 VBD program will be to operate a comprehensive program more efficiently (reductions were made to the 2012 budget), continue to review and refine the risk assessment process, and to implement program evaluation recommendations, once known.

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Glossary Ague A fit of fever or shivering or shaking chills, accompanied by malaise, pains in the bones and joints

BMP -Best Management Practices Components of an IVM program. Core BMPs for Ontario include: • Surveillance • Action thresholds, risk assessments, and decision-making • Physical and/or source reduction • Chemical control • Monitoring efficacy and resistance • Public education and outreach • Program evaluation • Record-keeping and mapping IVM - IVM Integrated Vector Management An inclusive mosquito control strategy that employs all available mosquito control methods individually or in combination to exploit the vulnerabilities of mosquitoes in order to reduce their numbers, while minimizing the impact to the environment. ECDC European Center for Disease Control FME - Features Manipulation Engine See Appendix A for more details KML – Google Keyhold Markup Language See Appendix A for more details MIEH McMaster Institute of Environment and Health MOHLTC Ministry of Health and Long-Term Care PHO Public Health Ontario PHS Hamilton Public Health Services

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Appendices

Appendix A List of Recent Contractors for Hamiltonâ&#x20AC;&#x2122;s WNV Program 2005 to 2011 Contract Eco-mapping

Evaluations (WNV program/comm unication campaign) GIS mapping software Larval identification/ surveillance training Larviciding Mosquito ID and viral testing

2005

2006

2007

2008

2009

2010

2011

In 2004 GDG Environmental began a habitat analysis and ecological mapping exercise which they completed in 2005 MIEH*

-

-

-

-

-

-

MIEH

MIEH

MIEH

MIEH

MIEH

MIEH

Geomedia Professional Annette Tavares

Geomedia Professional Annette Tavares

Geomedia Professional Annette Tavares

Geomedia Professional Annette Tavares

Geomedia Professional Annette Tavares

Geomedia Professional Annette Tavares

Geomedia Professional Annette Tavares

CCMM Cosray Labs

CCMM Cosray Labs

CCMM Cosray Labs

Pestalto Cosray Labs

Pestalto Cosray Labs

Pestalto Cosray Labs

Pestalto Cosray Labs

*McMaster Institute of Environment and Health

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Appendix B - GDG Mosquito Natural Habitat & Land Classifications Cattail Marsh - Marsh with cattail plants, generally shallow waters or highly water saturated soils. Ditch/Outfall - Roadside ditches, field drainage ditches, sewer network outfalls, small streams or clogged culverts. These will produce the same types of species. Field pool - Meadow marsh, fallow land, seasonally flooded with graminoids. Forest - Habitats that are seasonally flooded or easily flooded with rains; Silver Maple, Ash, Elm, Red Maple or Cedar wood. Marsh (wetlands) - Sites with emergent plants (Sedges, Bullrushes, Arrowhead), floating leaf plants (water lilies), or submergent plants (pondweeds). Mixed (Artificial) - Mixture of different habitats. Pond - Ravines, quarries, retention ponds, rivers edge, rockpools or lakeshore. Sewage Lagoon - Sewage treatment plants, lagoon perimeter and catwalks. Woodland Pool - Same as forest but with permanent pool. Creeks/Streams/Ravines â&#x20AC;&#x201C; a new category drawn from GDG habitat types of Ditches (streams) and Pond (ravines) was created in 2009 to organize types of moving or likely to be moving water into one habitat type. Escarpment Buffer - The line denoting the crest of the escarpment was buffered below the line feature by 300m and above the line feature by 100m. Catch Basin Buffer - The catch basin points were buffered by 100m. Natural Heritage layers - Contains categories Agriculture, Beach, Forest, Meadow, Successional, Water, Wetlands. The Urban category was removed for this analysis replaced by the Landuse layers. Landuse layers - Contains categories based on property codes Commercial, Industrial, Institutional, Mixed Use, Office, Open Space, Residential, Storage, and Utilities. The GIS habitat layer consists of mosquito habitat information that has been combined and drawn from various geographic data sources. Land area is represented by only one type of habitat which is determined by layering the prioritized habitats deemed a greater influence to contributing mosquitoes. When all layers are merged in priority order, it helps determine which habitats should remain when layers overlap, hence representing a geography by only one habitat type. The priority habitat layers are: 1. Sewage lagoons 2. Area of influence (100 metre buffered area) around the catch basin layer 3. Area of influence (300 metre buffered area) from the escarpment brow 4. The group of mosquito habitat types from GDG Environment Consultingâ&#x20AC;&#x2122;s eco-mapping project (2005) 5. The City Economic and Planning Department's Natural Heritage System mapping and Land Use cadastre mapping information 73


Appendix C Mosquito Trap Surveillance using Features Manipulation Engine Visualization of data through tools available from Google allow the Surveillance of West Nile Virus data to be shown in a timely and consistent format and seen using a variety of computer hardware with easy to use software. The popularity of Google products, such as Keyhole Markup Language (KML) and Google Earth, provides a familiarity to most users and the software is readily available for download with an internet connection. Additionally the Open GeoSpatial Consortium, an industry regulatory group, approved KML as an open standard for describing some geographic data. For the purpose of weekly surveillance, Google Earth is the platform used to display a digital file in the format of a KML. Google Earth is downloaded for free and already provides many tools and familiar map navigation buttons for the team to use in viewing the data. The KML file is opened in Google Earth and because the file is geographic based, it plots the locations relative to real world locations on Google Earth’s virtual globe. The benefit of a KML file is that it combines the location (to be placed on a map) and the descriptive information (mosquito counts by species and test results) about the mosquito traps each week for a summary on a per trap basis. Although not implemented in the 2011 season, the KML file can also be available for use on Google Maps viewable through a web browser (thin client) instead of the installed software like Google Earth (thick client). This would allow the data to be portable and retrieved through an internet connection using a mobile devise as well as desktop computers. A software package called Features Manipulation Engine (FME) from Safe Software is used to create the KML using a designed dataflow that brings tabular descriptive data and geographic locations of the mosquitoes traps together. The KML file is simply opened in Google Earth and rendered on the virtual globe overlaying mapping data and functional tools like Google Earth’s “Fly to” address finding, Street Navigation and Street View Google tools are also available for use in conjunction to the mosquito trap surveillance data. Because KML files are becoming a popular file format for geographic data visualization, other data sources can be retrieved on the internet to use as added background/supporting data as it relates to West Nile virus data. The KML file is capable of data visualization in three parts; 1.) geographic location of the traps represented using cartographic symbology to show the operational status and test results of the trap and it’s captured mosquitoes. 2.) graphs and charts to provide a summary of tabular data that would otherwise be overwhelming to comprehend. 3.) details about the trap

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The map objects for display by the KML are rendered on Google Earth’s virtual globe and will show an icon for the mosquito trap locations and active water site locations. The buffered area of 300 meters from the trap location and the delineation of the habitat types with in the buffered region is displayed with a coloured transparency so the Google airphoto can be viewed through the habitat areas. For added city related information, Ward boundaries are also displayed and they are identified by clicking anywhere in the city to display the ward number Using symbols with four different colour and sizes to show each trap’s test results for positive West Nile Virus vector carrying mosquitoes immediately allows the map reader to find the positive traps. Red and with a symbol size that is larger shows traps that are tested with a result of a positive WNV mosquito was captured in it. Yellow symbols indicate that the trap caught mosquitoes that were tested negative for WNV and smaller blue symbols indicate no mosquitoes were caught in those traps. Further to that blue symbols with a black dot indicate that the trap was in operation and fully functioning, but was unable to catch any mosquitoes. A blue symbol without a dot shows traps that were not in operation or no data was matched (trap data was not available). An example map is provided, below.

Many mosquito species with varying counts can complicate the interpretation of tables of data. Instead the application processes the data and presents it in a chart output. Each trap when clicked on will have a pop-out “balloon” that shows three charts of data. A pie chart shows the proportion of each group of mosquitoes species that that were captured. Another pie chart shows the

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proportion of surface land area by habitat type that can be found within 300m of the trap. A stacked bar chart shows the current year’s trend in counts of mosquito by species group as well as a line showing the historic weekly median of total mosquitoes over the trap’s years of service. There are other attributes displayed in the balloon that are used for quick reference: name of the mosquito specie(s) that was tested positive, number of pools tested from the trap, and added trap specific information about the trap that includes address, contact info and years in service. The FME program written for the WNV weekly assessment meetings displays data for a particular week number and year. Changing the “week” and “year” parameters will generate the status of the traps with its associated data for that time. The FME process requires less then 30 minutes to create the KML file. The process doesn’t require user interaction during the process once the Year and Week parameters are selected at the onset of the process. Maximum undivided attention to load the file, change the parameters and initiate the process would be less then 5 minutes. 5 minutes times 22 weeks in the WNV season would result in roughly 2 hours of GIS technician work given no changes to output are required. The KML output from the new FME software replaces the redundant efforts in creating a weekly map showing pie charts at each trap location using GeoMedia Professional GIS software with an output to static pdf. This map would require 1 ½ hours of time to generate each week. Considering the Pie Chart map over the WNV season would add up to 33 hours of work savings in total by the end of the season. Unmeasured efficiencies would stem from the use of the Google Earth tool in risk assessment, surveillance and monitoring of the West Nile Virus by the presenting the data visualization in an easy to read format, with spatial context and contained within one file- “one stop shop”. The FME software used to create the process was a new product to learn how to use. A steep learning curve would have added to the amount of time it took to design the workflow. To design and implement the process took a total of 100 hours. Cost recovery of in technician/analyst time for the program design would take three WNV seasons.

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Appendix D

West Nile Virus Communication Plan August 2011 Situational Analysis The West Nile virus (WNV) program for the City of Hamilton conducts many activities in order to assess risk to control West Nile virus locally as well as to communicate these risks to the community. By the end of the 2010 season there was limited West Nile activity in Ontario and Canada (Ontario with one (1) human case and Canada with five (5) human cases in total). Even with limited activity, the City of Hamilton has continued its baseline surveillance work and community outreach/education in 2011 to remain prepared to respond to positive results throughout the season. As of August 12 2011, the City of Hamilton has reported 13 positive mosquito pools. With the increased WNV activity, a three phase communication plan has been developed. Key Messages Public Health Services reminds residents to take personal precautions, including: ƒ ƒ

ƒ

Using a mosquito repellent containing DEET. Carefully follow manufacturer's instructions. Covering up when in known mosquito areas such as wooded areas, on the golf course, or in the garden, especially at dawn and dusk when mosquitoes are most active. Removing standing water on your property at least weekly to reduce mosquito development

Goal

The goal of the Hamilton Public Health Services’ WNV/VBD program is to reduce the risk of transmission to humans through the implementation of a communication plan that incorporates mass media, interpersonal communication and events. Audience Analysis/Insights As there is greater risk of contracting encephalitis from WNV infection in persons 50 years old or older, messaging should be targeted to baby boomers and seniors.

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Seniors/Responsible Generation: ƒ

ƒ

People from the responsible generation still prefer traditional media (e.g., TV, local newspapers, magazines) for news and information over new media (e.g., Internet, blogs, wikis). They are least likely (<5%) to use online blogging, chat rooms, social networks, and streaming video. 2 While not as popular with seniors as television, radio listening still occupies a lot of seniors’ time compared to other age groups. Radio may be especially useful in reaching women over 65. 3

Boomers: ƒ

Market research shows that while baby boomers trust their doctor most when it comes to health information, magazines and the Internet are not that far behind. 4

ƒ

Approximately 60 percent of boomers read a newspaper daily. This is substantially higher than other age groups. Advertising in newspapers to reach boomers, especially older boomers should be considered. 5

ƒ

Radio is also listened by Boomers, on average between 20 and 22 hours each week. Radio format preferences vary considerably based on age and gender; however Adult Contemporary is the most popular category of radio for Boomers, particularly women. 4

ƒ

In general, Internet use decreases with age but over 60 percent of households headed by a Boomer report using the Internet. 4

Activities The communication response for the WNV program varies as the risk to human exposure increases. Risk is measured by the presence of positive mosquito pools and positive human cases within a localized geographic area. Phase 1: These activities are implemented annually and are not influenced by the presence or absence of WNV activity in the community.

CDC Audience Insights. Communicating to the Responsible Generation (Aged 64-84) http://www.cdc.gov/healthmarketing/resources.htm#audience Visited on: August 15, 2011 3 The Health Communication Unit, at the Centre for Health Promotion, University of Toronto. Seniors Audience Profile. http://www.thcu.ca/infoandresources/seniorsaudienceprofile.htm Visited on August 17, 2011. 4 CDC Audience Insights. Communicating to Boomers (1946 - 1962). http://www.cdc.gov/healthcommunication/Audience/AudienceInsight_boomers.pdf Visited on August 17, 2011 5 The Health Communication Unit, at the Centre for Health Promotion, University of Toronto. Baby Boomers Audience Profile. http://www.thcu.ca/infoandresources/boomersaudienceprofile.htm Visited on August 17, 2011 2

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Phase 2: Activities in this phase include those implemented in Phase 1 with additional activities to provide increased community awareness of the presence of WNV activity in the City of Hamilton. Phase 2 is initiated by the presence and extent of the number of mosquito pools found positive with WNV. Phase 3: This phase includes activities implemented in both Phase 1 and 2 with additional activities to further increase awareness of the presence of WNV within a localized geographic area. This phase is initiated if there are surveillance factors indicating a higher level of risk to a localized geographic area See attached chart for activities implemented in Phase 1, 2 and 3.

Evaluation In the event Phase 3 activities are implemented, evaluation of a door to door campaign can be completed by mailing an evaluation tool (survey) to randomly selected residences identified by the Public Health Services Surveillance Unit.

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ACTIVITY Mass Media Outdoor Signage Online World Magazine Promotional Items Radio

PHASE 1

PHASE 2

Bus ads (August & September) Hamilton WNV website Seniors Review ad Pens 30 second radio ads & 10 second tags alternating weekly for four weeks among four of seven Hamilton stations run by the three radio companies serving Hamilton (Corus, Astral, Wave)

Newspaper

-

Continue Phase 1 Continue Phase 1 Continue Phase 1 Continue Phase 1 30 second radio ads & 10 second tags weekly for four weeks on four of seven Hamilton stations run by the three radio companies serving Hamilton (Corus, Astral, Wave) Community News ad

Tip Sheet

-

-

Direct Mail

-

-

Interpersonal Communications Telephone Enquiries Presentations Face to Face Events Fairs

Response to enquiries McMaster Geography Program Busker Fest – Dundas It’s Your Festival – Central Hamilton Peach Festival – Stoney Creek

PHASE 3 Continue Phase 1 Continue Phase 1 Continue Phase 1 Continue Phase 1 30 second radio ads & 10 second tags on all seven Hamilton stations for 4 weeks or extended run by the three radio companies serving Hamilton (Corus, Astral, Wave)

Spectator ad in addition to Phase 2 activities Post card delivered to residents in heightened risk areas Post card or letters may be mailed to residents in heightened risk areas in addition to or instead of door to door delivery

Continue Phase 1 As requested and if feasible -

Continue Phase 1 As requested and if feasible

Binbrook Fair in addition to Phase 1 fairs

Phase 1 and 2 activities

Door to door campaign within a geographic area

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Appendix E – WNV Tip Sheet

Front

Back

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Appendix F â&#x20AC;&#x201C; Lyme disease Fact Sheet

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Appendix G â&#x20AC;&#x201C; Public Notice of Application to Larvicide City of Hamilton Surface Waters for WNV Mosquito Control

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Appendix H - Communication Evaluation Tool

BINBROOK FAIR 2011 WNV MEDIA CAMPAIGN TRACKING SHEET DATE:_________________________ 1. Do you think radio is a good way to educate the public?

YES

NO

UNSURE

2. Do you have a favourite radio station?

RADIO STATION AM 820- CHAM, 820 CHAM (country) AM 900- CHML, (news/talk) AM 1150- CKOC (oldies) FM 93.3- CFMU, Mac Campus Radio FM 94.7- CHKX, KX 94.7 (country) FM 95.3- CING, Vinyl 95.3, classic hits FM 101.5- CIOI, Mohawk Campus Radio FM 102.9- CKLH,K-Lite FM, adult contemporary FM 107.9- CJXY, Y108, active rock

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3. Have you heard/seen any WNV messaging this year?

YES

NO

4. If yes, where? TV WEBSITE BUS SHELTER BUS BILLBOARD MAGAZINE NEWSPAPER

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Appendix I - Lyme disease Evaluation Tool HAMILTON PUBLIC HEALTH SERVICES Vector Borne Disease Program 2011 Let’s Target Lyme! Festival Name: _______________________________________ Date of Interview:

Month/Day_________________________

FOUR QUESTIONS

1. Have you heard of Lyme Disease?

Yes

No

2. What causes Lyme Disease?

Tick

Doesn’t know

Said someth ing other than tick

3. Do you know what a tick looks like? If no, show tick Yes No

4. Have you seen any ticks in Hamilton this year?

Yes- if yes where? No Name intersection or place or address?

1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 86


Appendix J

Website Data Analysis

2011

Prepared by McMaster Institute of Environment and Health (MIEH) K. Bruce Newbold, Director newbold@mcmaster.ca Marie McKeary, Research Facilitator mckear@mcmaster.ca

For Susan Harding-Cruz, Manager sharding@hamilton.ca VECTOR BORNE DISEASE PROGRAM

HEALTH PROTECTION DIVISION PUBLIC HEALTH SERVICES HAMILTON, ONTARIO January 2012

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WEBSITE DATA ANALYSIS 2011

An important aspect of evaluating the public education and community outreach mandate of the West Nile Virus (WNV) program is to examine website usage, essentially, the ‘traffic’ occurring at the local WNV website http://www.myhamilton.ca/myhamilton/CityandGovernment/HealthandSocialServices/PublicHeal th/WestNileVirus/). The total number of web views (‘hits’) of WNV program pages is one indicator of public interest/concern with regards to the vector borne virus. the traffic directed to ‘targeted’ pages within the site is an indicator of the priority needs of the public in terms of WNV. The pages traditionally ‘targeted’ for analysis, were originally chosen for their focus on Personal Protective behaviour/information or Control/Surveillance measures implemented by the program management and staff. The development and architecture of the WNV website is a collaborative creation of the WNV program manager and staff and the HPHS Information Technology (IT) department. The following report analyzing site usage (‘traffic’) and patterns has been conducted by research consultants at the McMaster Institute of Environment and Health (MIEH), on an annual basis from 2006 till the present. 6 Website statistics reflect both internal and external user activity. Thus, the site users are a combination of PHS and City of Hamilton staff, as well as members of the general public. During the second half of 2011 (August to December) the IT department for Hamilton Public Health Services contracted with a new provider for data retrieval, subsequently, this led to changes in both potential data analysis, as well as the ability to compare data from previous years with the current year. Although data for the total number of ‘hits’ would still be available, entry/exit ‘hit’ data would necessitate a new analysis. The WNV site is composed of multiple pages offering information on numerous aspects of the program including: surveillance statistics, program information, general information on WNV and children, larviciding notification, Q/A larviciding and adulticiding, report activity of dead birds by the public, standing water (both remove and report), and protection and prevention information. In recent years, the staff has added information on Lyme Disease and an Adult Mosquito Registry. The following report will examine specific ‘targeted’ pages within the context of overall website activity for the Vector Borne Disease (VBD) program (formerly the WNV program). The ‘targeted’ pages offer advice on personal protection, outline the city wide surveillance and control program implemented by HPHS, track the results of the surveillance activity, which is required by the Ministry of Health and Long Term Care (MOHLTC), and the index page (which is the default ‘home’ page). The overall total number of hits (2006-2011) to the WNV website both targeted and non-targeted within Public Health Services are listed below for comparison purposes: ¾ ¾ ¾ ¾ ¾ ¾

2006 = 33,084 2007 = 22,765 2008 = 18,517 2009 = 13,362 2010 = 14,011 2011 = 6,808

6

MIEH acknowledges the invaluable assistance of Ramsin Kamos, Application Analyst for Hamilton Public Health Services for his retrieval of WNV data.

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The total number of hits for targeted pages only (selection criteria discussed earlier in report), are

as follows: ¾ ¾ ¾ ¾ ¾ ¾

2006 = 17,172 (approx. 52% of total) 2007 = 13,473 (approx. 59% of total) 2008 = 11,334 (approx. 61% of total) 2009 = 8,039 (approx. 60% of total) 2010 = 10,224 (approx 73% of total) 2011 = 5,077 (approx. 75% of total)

Table 1 examines the individually selected targeted pages’ for the years 2006-2011. These pages were originally ‘targeted’ as those specifically focusing on prevention/protection at both an individual and program level. Over time, analysis has revealed these pages increasingly hold the greatest interest for the general public (steadily increasing from 52%-75% of total surveyed pages, as of 2011). The first column of Table 1 outlines the web address (URL) used to connect to the specific web page. Subsequent columns give a description of the information found on the web page and the number of ‘hits’ to that page, included as a percentage of the annual total, over the last six years (2006-2011), for comparison purposes. It should be noted, since the website is a fluid and ever-changing document, that for the years 20082010 there were a number of changes to the web site and consequently, the analysis. Q/A WNV, children, and Links were added to targeted pages. In July 2009, the VBD program team developed an “Adult Mosquito Registry”. This web page allows adults to register with Public Health Services activating an automatic notification system, which will electronically contact each person registered by their chosen method of communication (telephone, email system, fax, etc) regarding any immediate plans to adulticde in their area. Thus, the program management addresses the concerns of environmentally ‘sensitive’ adults. In 2010, the Ministry of Health and Long Term Care (MOHLTC), the administrative and regulatory body for Public Health units in Ontario, changed the name and mandate of the WNV program in Ontario, to the more encompassing Vector Borne Disease (VBD) program. Program staff would now be responsible for Easter Equine Encephalitis (EEE), Lyme, and Malaria, etc. amongst others. Program management developed an additional web page on Lyme Disease to reflect these changes. The Lyme Disease page was subsequently included in the surveillance project as a ‘targeted’ web page. All of the targeted pages for the years 2006-2011 are listed in Table 1. Among selected targeted pages the ‘Home’ page (‘index’) is included as an indicator of interest in WNV generally (it is often found as the ‘entry’ vehicle utilized by visitors – as discussed later in the report) and analysis of the data reveals larger numbers to this site. After the Home page (2,443 hits) the most popular pages for 2011 including Lyme Disease (622 hits) and Q/A general (418 hits). Thus, overall the public demand continues in terms of accessing information regarding both WNV (with the goal of understanding for the purpose of personal protection, as well as interest in the surveillance/prevention activities of the program) and new and emerging concerns, such as Lyme disease.

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Table 1 TARGETED WEB PAGES Within the WNV site

PAGES AND HITS

WEBSITE ADDRESS

DESCRIPTION OF INFORMATION FOUND ON PAGE

WNV 2011 2010 2009 2008 2007 2006 Annual Comparison

TOTAL WEBSITES HITS

1)PublicHealth/WestNileVirus/index.htm

Home page for the WNV web pages. (default)

2443 (48%) 4617 (45%) 4236 (53%) 5,761 (51%) 1,471 (33%) 8,540 (26%)

2)PublicHealth/WestNileVirus/Reduce-Exposure.htm

Reduce exposure to mosquito bites including personal protection information.

3)PublicHealth/WestNileVirus/WNV-inHamilton.htm

Prevention plans in Hamilton/reducing the risk to WNV

172 (3%) 481 (5%) 143 (2%) 889 (8%) 1,229 (5%) 1,471 (4%) 226 (5%) 530 (5%) 630 (8%) 636 (6%) 1,112 (5%) 1,489 (5%)

4)PublicHealth/WestNileVirus/History.htm

Surveillance statistics

361 (7%) 563 (6%) 567 (7%) 760 (7%) 1,175 (5%) 1,598 (5%)

5)PublicHealth/WestNileVirus/Important-Facts.htm

Transmission/symptoms/City of Hamilton plans for reduction/Malathion

223 (5%) 519 (5%) 561 (7%) 730 (6%) 1,119 (5%) 1,466 (4%)

6)PublicHealth/WestNileVirus/QA-General.htm

Transmission/Symptoms/Type of mosquito/time of day, etc

418 (8%) 778 (8%) 735 (9%) 1,061 (9%) 1,311 (6%)

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TARGETED WEB PAGES Within the WNV site

PAGES AND HITS

WNV

2011 2010 2009 2008 2007 2006 Annual Comparison

1,644 (5%) 7) PublicHealth/WestNilevirus/qa-wnv-andchildren.htm

Outlines information on WNV and children including prevention, protection, and treatment options.

8) PublicHealth/WestNilevirus/links.htm

Various website links to public health and other agencies involved with WNV includes provincial, national, and international links.

9) PublicHealth/WestNilevirus/adultmosuitoregistry.htm

Adults register with PHS and are electronically notified when any adulticiding is to occur in their geographic area.

10) PublicHealth/WestNilevirus/lymedisease.htm

Details information on the prevention and control of Lyme Disease. As well as guidance for ‘tick’ identification

(2011) 262 (5%) (2010) 739 (7%) (2009) 675 (8%) (2008) 916 (8%) (2011) 188 (4%) (2010) 491 (5%) (2009) 492 (6%) (2008) 581 (5%) (2011) 156(3%) (2010) 473 (5%) (2009 –Aug-Dec) 157 (.02%) (2011) 622 (12%) (2010) 1031 (10%)

Total number of targeted hits for time period 20102010.

(2011) 5077 (75%) (2010) 10,224(73%) (2009) 8,039(60%) (2008) 11,334(61%) (2007) 13,473(59%) (2006) 17,172(52%)

OVERALL, total number of hits for the years, 20112006.

2011 - 6,808 2010- 14,011 2009- 13,362 2008- 18,517 2007- 22,765 2006- 33,084

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DATA ANALYSIS of ‘TARGETED’ PAGES Each year data is collected and analyzed by MIEH consultants regarding web site usage ‘traffic’. The results of the surveillance project are utilized by program management to fulfill Ministry requirements by submission of an annual report, as well as, aiding in evidence based decision making in the allocation of program resources in the most efficacious manner and in the development of the annual education and public awareness seasonal campaigns. In recent years, there has been a decrease in the total number of web hits. 2010 was an exception to the pattern revealing an increase from the previous year (2009-13,362 to 2010-14,011). 2011 revealed a decrease similar to previous years’ data (2011 – 6,808). Although data reveals a decrease in visitors to the website, the WNV pages still collected approx. 6,808 views. The corporation of the City of Hamilton has an estimated 6,700 web pages for potential viewing and interest in the WNV website should be viewed within this context. Later in the report, we will also draw attention to the ‘ranking’ of the pages in comparison to the popularity of the other potential topics/views available. When we consider the variety of public health concerns introduced to the population in recent years, eg. HINI, WNV/VBD is evidently still of interest to the general public. The WNV program of Hamilton Public Health Services (HPHS) began in 2001, and continues to deliver a comprehensive and evidence-based education and outreach campaign (as well as surveillance and protection) dependent on available financial resources. With regard to the ‘targeted pages’ public interest would appear to be focused (similar to previous years) on those pages focused on both protection and prevention measures at both an individual and program level. Based on scientific evidence the province has designated May until October as the time period/season to be most cautious in terms of the potential of WNV. During this time period, we consistently found a marked increase in web site ‘traffic’ as reflected in the total number of targeted hits (Table 2 ). These findings substantiate the claim that, public concern continues to be invested with regard to WNV/VBD diseases. This finding will also be substantiated when we examine other aspects of the website including, Entry and Exit website activity. Although there has been some decline over the years, Table 2 is a testament to the continued interest by the public in WNV, and in 2010/11 also for Lyme Disease. As stated previously, website ‘traffic’ to the WNV pages increases over the designated WNV season (May to October or the occurrence of the first two frosts). Other interesting occurrences of increased traffic include:

January 2006, 2008, 2009 and 2011, December 2007 and 2009, and both 2006 and 2009 had an early increase during the winter season and accompanying decrease earlier in the season starting in July/August. It would be worthwhile to contrast these observed patterns with

climate/weather patterns for the identified years. The current year, 2011, reveals that public interest in the WNV website appeared to ‘peak’ over a shorter time period, specifically June through August, which were also particularly ‘hot’ months in terms of temperature in the Hamilton area. It is interesting to note there was also an interest early in the 2011 season, January through March.

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Table 2 MONTH

January February March April May June July August September October November December Total Number of Targeted Hits 2006-2011

# of Targeted Hits WNV 2006 7% (1187) 7% (1153) 10% (1710) 10% (1636) 12% (2022) 12% (2052) 9% (1570) 11% (1834) 7% (1162) 6% (1060) 5% (940) 5% (849) 17,172

# of Targeted Hits WNV 2007 7% (920) 6% (859) 8% (1053) 8% (1057) 10% (1407) 12% (1627) 13% (1704) 10% (1366) 9% (1201) 4% (547) 6% (764) 7% (968) 13,473

# of Targeted Hits WNV 2008 6% (719) 6% (640) 6% (681) 6% (695) 9% (990) 12% (1407) 12% (1401) 13% (1482) 10% (1126) 7% (777) 7% (809) 5% (607) 11,334

# of Targeted Hits WNV 2009 8% (665) 9% (716) 11% (850) 8% (638) 11% (871) 11% (847) 10% (811) 9% (755) 7% (593) 7% (530) 2% (195) 7% (568) 8,039

# of Targeted Hits WNV 2010 7% (698) 5% (542) 7% (704) 6% (648) 8% (821) 17% (1738) 12% (1269) 7% (699) 6% (596) 5% (528) 14% (1400) 6% (581) 10,224

# of Targeted Hits WNV 2011 13% (672) 11% (538) 10% (495) 6% 328 8% 400 12% 591 12% 610 15% 765 7% 368 3% 132 2% 100 2% 78 5,077

This past year, the program recorded two (2011-2) cases of human WNV infection, which is double the number, recorded in recent years. Overall, the program has recorded the following human case numbers: 2002 – 18, 2003 – 4, 2006 – 3, 2004-2010 – either 1/0. 2011 also saw a sharp increase in ‘positive’ mosquito pools from the past few years. There were a recorded thirty-one (31) positive mosquito pools, which is the highest, noted since the inception of the program. Only the fourteen (14) positive mosquito pools recorded in 2006 and the eleven (11) recorded in 2002 came close to this number. The program management and staff are monitoring this increase with vigilance. The change in surveillance results is also noteworthy in the context of the findings of a 2011 report published by the European Center for Disease Prevention and Control (ECDC) to be discussed later. ENTRY PAGES Definition: Entry pages are the website pages used by individuals to enter the WNV site in 2007 – 2011. However, there were changes in the retrieval and reporting of data as of the midpoint of 2011 (August – December) and in the completed format of the data report. Due to these changes in data retrieval at midyear entry and exit web page hits were not comparable to previous years. Thus, analysis was necessarily separated over the two halves of 2011. Most Popular Entry Pages within the WNV site 2007-2011 It is also interesting to examine the actual pages (identified by URL addresses) and utilized by individuals as they enter the WNV site and search for any patterns, which may exist. The Lyme Disease page of the WNV site continued to be popular in 2011 (similar to the year of its inception in 2010). In the first part of the year, May (43 hits), June (41hits), and July (20 hits) recorded the highest number of hits to the Lyme Disease webpage. For the second half of the year (AugustDecember) the new data retrieval system allowed the researchers to rank order (estimate the ‘popularity’) of individual web pages within the larger number of approximately 6,700 potential web pages contained within the corporation of the City of Hamilton portal. The WNV Homepage (as an indicator of the public interest) ranked consistently high throughout the second half of 2011 (August – 142/6,700 (r), September 343 (r), October 708 (r), November 974 (r), and finally, December 845/6,700). The Lyme Disease page ranked second highest in popularity among WNV web pages for the second part of the year (August – 918/6,700 (r), September 1029(r), October 827(r), November 1264(r), and finally, December 903/6,700). 93


EXIT PAGES Definition: Exit pages are the website pages viewed last by individuals leaving/exiting the WNV site in 2007 -2011. However, there were changes in the retrieval and reporting of data as of the midpoint of 2011 (August â&#x20AC;&#x201C; December) in the format of the reported data. Due to these changes in data retrieval at midyear entry and exit web page hits were not comparable to previous years. Thus, analysis was necessarily separated over the two halves of 2011. Most Popular Exit Pages within the WNV site 2007-2011 It is also interesting to examine the actual pages (identified by URL addresses) and utilized by individuals as they exit the WNV site and search for any patterns, which may exist. The Lyme Disease page of the WNV site continued to be popular in 2011 (similar to the year of its inception in 2010). In the first part of the year, the Lyme Disease webpage, for May (57 hits), June (61 hits), and July (30 hits) recorded the highest number of exit hits. This increased interest in both the WNV Home page and Lyme Disease for entry/exit pages implies visitors may have accessed all the information needed at these two sites or searching the WNV site with very specific needs. For the second half of the year (August-December) the new data retrieval system allowed the researchers to rank order (estimate the â&#x20AC;&#x2DC;popularityâ&#x20AC;&#x2122;) of individual web pages within the larger number of approximately 6,700 potential web pages contained within the corporation of the City of Hamilton portal. The WNV Home page ranked high for the months of August ranked 245 (r), September 589 (r), and October 877 (r) out of the potential 6,700 City of Hamilton web pages. Other highly ranked exit pages included, Surveillance, General Q/A and Lyme Disease.

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ADULT MOSQUITO REGISTRY From July of 2009 until the present year, the WNV website included the addition of an Adult Mosquito Registry The registry allows individual members of the public to enter their personal contact information and have the WNV team send them advanced notification of any plans to apply Malathion in their residential area. Should it be determined that adulticiding is necessary to control the spread of WNV, Hamilton Public Health Services is committed to notifying residents in the affected areas a minimum of forty eight (48) hours in advance of the application. Although the Registry was created late in 2009, it immediately attracted public interest as evidenced by the web site activity listed for 2009. This interest continued into 2010 and 2011, with the largest interest in 2010. It would be due diligence to continue to monitor public interest in the Registry.

Table 3 Adult Mosquito Registry Web site Activity January February March April May June July August September October November December Total

Hits 2009

Hits 2010

Hits 2011

N/A N/A N/A N/A N/A N/A N/A 31 43 28 13 42 157 % of Targeted Pages = 2%

32 22 33 31 48 102 44 29 23 28 56 25 473 % of Targeted Pages = 5%

26 25 14 8 6 21 24 13 8 4 3 4 156 % of Targeted Pages = 3%

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Lyme Disease As mentioned in the introduction, the program now encompasses not only WNV but other vector borne diseases, and in response, the VBD program staff, beginning in 2010, created an information page on Lyme Disease. The page offers background information, identification (of ticks), prevention, and treatment information on the disease. Activity on the web page indicates an active interest on the part of the public since the site has been one of the most popular among the selected targeted pages since its inception (accounting for 10% of total hits to targeted pages in 2010 and an increase to 12% of targeted pages in 2011). Although the raw number of hits is less in the second year, proportionally speaking in terms of total interest in WNV sites, the page has increased in interest. The researchers suggest program staff continue to track website activity to this page as an indicator of the public interest in a new and emerging disease of concern.

Table 4 Lyme Disease Web site Activity January February March April May June July August September October November December Total

Hits 2010 52 49 57 84 140 204 149 56 51 49 91 49 1031 % of Targeted Pages = 10%

Hits 2011 73 45 56 38 94 113 74 26 27 29 29 18 622 % of Targeted Pages = 12%

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ECDC – a Lesson in Complacency? In 2011, the European Center for Disease Prevention and Control (ECDC) released their first Mission report on WNV surveillance in Europe. 7 A number of outbreaks in 2010, had occurred after a lengthy period of dormancy (with only sporadic cases reported) which became the catalyst for a review and reassessment of the current ‘risk’ potential and subsequent response in terms of WNV for the European organization. The most severe outbreak occurred in Romania but there were also outbreaks in Greece, Russia, amongst others during 2010. The impetus for the report was a reassessment of the potential risk of the disease in the light of the series of outbreaks. The Romanian outbreak was notable both for the number of human cases reported and that it occurred after the country had experienced a decade long period of dormancy. In 2010, there was a change in the epidemiological situation and by October 13, 2010; there were 47 confirmed cases of WNV infections (included two deaths). The reporting period included July to September 2010. More importantly, for the first time in more than ten years, the geographic locations of reported

cases included counties in the central and northern part of the country.

The variables implicated in fatalities/infections included age (60+) and gender (higher incidence between males than females). During the epidemiological investigation, all confirmed cases were interviewed for the occurrence of a series of potential risk factors for WNV infection. Of these, 87%

reported mosquito bites, 30% reported stagnant water around their residence, 21% reported gardening as a leisure activity, and 30% reported rearing poultry.(ECDC,2011) Entomological

surveys were carried out collecting mainly resting mosquitoes with different types of aspirators and some active mosquitoes with different type of traps. Of the 3,689 mosquitoes collected, 94–96% were Culex pipiens, and one pool of Cx. pipiens resulted in WNV antigen positivity.

The ECDC/WHO team found similarities between the 2010 Romanian outbreak and a 2010 outbreak in Greece, both outbreaks showed the peak of the outbreak towards the end of August, eventually tailing off in September. This suggests that the conditions in 2010 were equally favourable to the circulation of WNV in Greece and Romania. It is unconfirmed whether these conditions were due to climatic factors (rainfall, temperature, humidity, etc.), the lineage of virus introduced, bird migration, mosquito vectors involved, etc., overall the report states it may be one

or more of these variables.

Since the goal of the mission report compiled by the ECDC/WHO was to develop a risk assessment not just for Romania but also the rest of Europe, they conclude, ‘considering the outbreak in both

Greece and Romania in the same year, it is clear that ecological parameters in parts of Europe are currently favourable for viral activity.’ 8(ECDC,2011) Furthermore, support for this

assumption comes from reports of human outbreaks, which occurred during the same time period in Russia and Hungary, and equine outbreaks in Morocco. “Thus, the need for strengthened

surveillance as well as preparedness plans that cover all aspects involved in the transmission of this disease, including human surveillance, entomological surveillance, veterinary surveillance (including birds and horses), and blood and tissue safety are recommended.”(ECDC,2011) The Local Connection MIEH has partnered with the Hamilton VBD (formerly the West Nile Virus) program for the past six (6) years and is familiar with the program surveillance/outreach activities and reported statistics. Since the inception of the program the source reduction and prevention component of the program has met with success, with the result being less human cases than in the early years of the program (2002 is the date of inception for the program). Thus, we believe the information gathered by ECDC/WHO in their mission report regarding the Romanian outbreak, could benefit the Hamilton 7

European Centre for Disease Prevention and Control/WHO Regional Office for Europe. West Nile virus infection outbreak in humans in Romania, 2010. Stockholm: ECDC; 2011.

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PHS Program Manager in terms of both on-going and future planning of the Hamilton V.B.D. program. In particular, the primary lesson may be the importance of continued vigilance

considering the severity of the Romanian outbreak, which was preceded by a ten (10) year period of dormancy. The goal of the Hamilton program is to minimize the impact of WNV

through district-wide surveillance that directs integrated pest management based mosquito control activities at a level commensurate with the risk of human illness. This means an emphasis on surveillance, public education, and source reduction. Surveillance includes collecting and identifying sample pools of mosquitoes, again, referring back to the Romanian report, this activity was essential during the outbreak for identification and tracking purposes. Unlike, Romania, these activities are currently mandatory and guided by the Ontario Ministry of Health and Long Term Care (MOHLTC).

As stated earlier in this report, in 2011 the local Hamilton program saw not only a notable increase in the number of ‘total positive mosquito pools’ as of August (97% increase from 2010 – more importantly the highest since inception of the program in 2000) but experienced its highest number of confirmed human cases since 2006. All of the risk factors identified during the Romanian epidemiological investigation have always been the focus of the education and outreach component of the program of HPHS/WNV since its inception (with the exception of ‘rearing poultry’.) Epidemiological investigation of confirmed cases, during the Romanian outbreak, indicated the following risk factors; mosquito bites, stagnant water near residences, leisure gardening and rearing poultry. Program outreach by Hamilton PHS traditionally has two primary message streams, the first being educating and identifying risk activities and secondly, advocating individual protection measures, including applying insecticide, awareness of dusk till dawn vulnerability and wearing protective clothing while participating in outdoor activities (the program also implements population level protective measures, eg. larvaciding). Hamilton also has a Standing Water By-Law, which takes effect from April 1 to October 31 each year, the time period, which encompasses WNV season. The reporting period for the Romanian outbreak included July 4 till September 13, 2010 with the majority of cases reported in the month of August (65%). Although the Hamilton program is active throughout the year, as previously stated the major focus of WNV activities occurs from May to September. Thus, it would appear to be prudent for the Hamilton PHS program to not only continue its prevention and surveillance activities at the local level but also its education and outreach activities. Continuing to raise awareness among the Hamilton public and building on the public interest evidenced by the website traffic activity will enable the program to draw upon that knowledge should the epidemiological conditions found in Europe in 2010 duplicate themselves locally.

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SUMMARY/RECOMMENDATIONS for WNV/VBD WEBSITE ‘TRAFFIC’ DATA An analysis of website ‘traffic’ data first collected in 2006 has occurred annually until the present year. This data retrieval and analysis allows for the establishment of patterns, which reveal a continuing public interest in both WNV and other emerging vector borne disease, as well as, the work of the WNV/VBD program management and staff. In conclusion, although there has been some decline in website ‘traffic’ on the WNV/VBD site, it continues to be a popular destination within Hamilton Public Health Services web based program information sites and within the larger corporate City of Hamilton web portal. Over the last ten (10)years of the Hamilton program, public interest in both WNV and the activities of the WNV program, continue as evidenced by the parallel of increased website traffic over the designated WNV peak season of May to September. In particular, there appears to be continuing public concern with regards to WNV Prevention/Protection and Control/Surveillance activities. There is also an interest in any new and emerging vector borne diseases as evidenced by the website traffic on the new Lyme Disease web page in 2010 and 2011. The WNV program team, since its inception in 2001, has continued to offer a comprehensive program focused on the two major components of Protection and Prevention via both Education/Outreach and Surveillance activities. It is also worth repeating the recommendation of the ECDC in their first comprehensive WNV Mission report published in 2011:

Thus, the need for strengthened surveillance as well as preparedness plans that cover all aspects involved in the transmission of this disease, including human surveillance, entomological surveillance, veterinary surveillance (including birds and horses), and blood and tissue safety are recommended. Based on the findings detailed in the preceding report, the McMaster Institute of Environment and Health (MIEH) recommends that financial resources permitting:

Hamilton Public Health Services continue to track website ‘traffic’ activity and continue its consultancy agreement with the McMaster Institute of Environment and Health (MIEH) to conduct an analysis of the data to monitor ‘consumer need’ for information, to maintain current public awareness levels and remain vigilant in the event of potential epidemiological changes in WNV, and subsequently, to prioritize the distribution of program resources including Web site design and development and other outreach/educational activities.

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Vector Borne Diseases Annual Report, 2011