ABSTRACTS

SESSION6.3:ONEHEALTHAPPROACHFORMONITORINGAMR:ACASESTUDYINNEW CALEDONIA

a.Institut Pasteur de Nouvelle-Calédonie, Pôle de Bactériologie, Groupe de Bactériologie Médicale et Environnementale, CEDEX BP 61, Noumea 98845, New Caledonia bBacterial Symbionts Evolution, Centre Armand-Frappier Sante Biotechnologie, Institut National de la Recherche Scientifique, Universite du Quebec, Laval, Canada cThe Pacific Community, Public Health Division, Noumea, New Caledonia d.Centre Hospitalier Territorial Gaston-Bourret, Laboratoire de Biologie Médicale, CEDEX BP J5, Noumea 98849, New Caledonia

The rapid emergence and spread of (multi)resistant and pathogenic bacteria is a priority health issue. Despite their insularity, the Pacific Island Countries and Territories have not been spared by this pandemic. In New Caledonia, the surveillance of antimicrobial resistance traits was historically investigated through clinical studies, based on large numbers of samples from individual patients toprovideepidemiologicaldata.

Overthepastdecade,wastewatersurveillancehasbeenincreasinglyusedtoreflectthepopulation's gut microbiota, raising the possibility of using wastewater-based epidemiology to directly gain information about antimicrobial resistance In this context, carbapenemase-producing Enterobacteriaceae, classified as priority pathogens by the WHO and implicated in hospital outbreak in New Caledonia have been isolated from clinical and wastewater sample. Given the diversity of resistant bacteria in wastewater, carbapenemase-producing Enterobacteriaceae were isolated using an easy-to-apply phenotypic method developed in our lab Several isolates were whole genome sequenced to identify the repertoire of lineages, genes and mobile genetic elementsinvolvedincarbapenemsresistanceinNewCaledonia.

Ourfirstresultsindicatedanimportantdiversityamongbacterialstrains,andthepredominanceof specific associations of beta-lactam resistance genes and mobile genetic elements. Several genes wereonlydetectedinenvironmentalsamplesbeforetheirdetectioninclinic,highlightingthevalue of this One Health approach for AMR surveillance. Resistance genes and mobile genetic elements identifiedinthisfirstprojectwerecloselyrelatedtothosefoundintheAustralianbacterialisolates. Finally, to complete inventory of antibiotic resistance in New Caledonia, the animal compartment willbeinvestigated.

In addition to the results generated in terms of epidemiology, these results are also important for authorities in terms of knowledge about resistance mechanisms circulating in the country and to optimizetheconsumptionofantimicrobials.

SPEAKERPROFILE: DrBourlesAlexandre

Bourles Alexandre is an Engineer in Medical and Environmental Bacteriology Group at InstitutPasteurofNewCaledoniasince2020 Hisresearchactivitiesfocusonantimicrobial resistanceandmorepreciselyonthedisseminationofantimicrobialresistanceusingOne Health approach. Culture and metagenomics approaches are used to track multi drug resistance bacteria from several sources (hospitals and the community) down to the coastalareaallthroughthewastewaternetwork

SESSION 7.1: EXPLORING THE RESISTOME IN SEDIMENT-ASSOCIATED BIOFILMS FROM RURAL FIJIAN WATERSHEDS: MICROBIAL ECOLOGY INSIGHTS FROM THE WATERSHED INTERVENTIONS FOR SYSTEMS HEALTH IN FIJI PROJECT (WISH -FIJI)

Aaron Jenkins, Gemma C Langridge, John Wain, Lisa Crossman, Stacy Jupiter, Joel Negin, Ponipate Baleinamau, SikeliGavidi,KiniKotoMailautoka,SamuelaLagataki,SangeetaMangubhai,KeleraNaivalu,TimociNaivalulevu,Vilisi Naivalulevu, Nabeela Nasim, Sikeli Naucunivanua, Sarah Nelson, Ingrid Qauqau, Anaseini Ratu, Mereia Ravoka, ShayalSami,JacquelineThomas,AndrewTukana,AnaseiniRatu,DonaldWilson,PierreHorwitz

Background: Our work has shown that some rural watershed settings in Fiji, particularly those prone to anthropogenic activity resulting in soil erosion and sedimentation, are more likely to be associated with high water-related microbial disease burden than others Biofilms dominate microbial life in aquatic systems, and bacteria living in biofilm communitieshaveincreasedresistancetoantibiotics.Biofilmsareattachedtolivingtissuesurfacesandabioticsubstrates and can also form microaggregates such as flocculated suspended and bed sediment particles. WISH-Fiji has been developing sampling and metagenomic methods for environmental surveillance of microbial pathogens and understandingtheresistomewithinruralwatershedsettings,withafocusonsediment-associatedbiofilms.

Methods: 4L river water samples and 025g river sediment biofilm samples were collected from five Fijian watersheds along a spectrum of anthropogenic activity and waterborne microbial disease burden. Water samples were vacuum filtered to 0.2 μm and DNA extracted from filters,and directly from sediment using Qiagen Power Water and Power Soil kits,respectively 103samplesfromthestudywatershedswereputforwardforpreliminarymetagenomicssequencingon theIlluminaMiSeqplatform.SequencingdatawereprocessedusingKraken2fortaxonomicclassificationandFastDeMe foridentificationofantimicrobialresistance(AMR)determinants.

Results:Microbialcommunitiesinwaterandriverbedsedimentbiofilmsinhighlyanthropogenicallyalteredwatersheds have distinct community composition, including increased abundance of several bacterial groups, particularly Gammaproteobacteria (including Salmonella) and reduced beta diversity (among identifiable taxa), Enterobacteriaceae association with bacterial group Acinetobacter (of concern due to rapid antimicrobial resistance development and long environmentpersistence),abundantAMRgenepresence,andincreasedbacteriacapableofmetabolizingplantmaterial. This set of samples yielded 3702 occurrences of 831 AMR genes encoding resistance to a broad range of antibiotics includingbeta-lactams.

Conclusions: Our results collectively suggest that increased sedimentation, nutrient runoff, and algal growth in waterways due to human activity alters the microbial community improving ecological conditions for enteric bacterial growthandpersistence.Biofilmsonsedimentprovideamicro-nicheforbacterialsurvivalandreplication,withnutrients readily binding sediment particles and sugars conducive to bacterial growth being released from algae. The eutrophication of waterways and subsequent formation of algal mats on sediment provides an excellent substrate for bacterialgrowth,particularlybiofilmformation,associatedwithenhancedantibioticresistance.

SPEAKERPROFILE: DrAaronJenkins

Dr Aaron Jenkins is a mid-career researcher and Fijian citizen with a joint postdoctoral appointment as Senior Research Fellow in Planetary Health at University of Sydney School of Public Health and Edith Cowan University Centre for People, Place and Planet Dr Jenkins is also an adjunct researcher with Fiji Centre for Communicable Disease Control, Fiji National University, and University of the South Pacific Dr Jenkins is an eco- epidemiologist with 23 years of professional experience in international development working in Fiji, Papua New Guinea, Solomon Islands, Palau, Samoa, Kiribati, Vanuatu, Federated States of Micronesia, Indonesia, Philippines, and Australia. His research has focussed on crosscutting development themes including wetland management for Water, Sanitation and Hygiene (WASH), waterborne disease management, integrated conservation and development, interaction of climate change, natural disaster, land and water management on humanhealthandsustainablefisheries.DrJenkinshasanexcellentrecordofbuildingpartnerships across sectors and communities including key relationships between donors, regional agencies, governments and communities across the Indo-Pacific region He also has a high level of engagement in international, regional and development affairs including committee membership and advisory roles for WHO, CBD, UNICEF, UNDP, IUCN, SPC, SPREP as well as numerous national environment, health and WASH related committees in Fiji, Papua New Guinea, Palau, and Solomon Islands.