Page 1

STEPs—Simple Tools for Effective Protocols

Vector-borne Disease Screening

Protocol Implementation

Suggested vector-borne disease screening guidelines

SNAP® 4Dx® Test Screen your dog every year with the SNAP 4Dx Test to detect exposure to pathogens that cause heartworm disease, ehrlichiosis, Lyme disease and anaplasmosis.

Your pet’s screening result and what it means Depending on the results of your pet’s wellness screening, additional testing or therapies may be required.

Positive result The dog has been exposed and may be infected

? What to

Run additional tests to confirm infection

do next?

Clinical signs and/or laboratory findings indicate either

1 Diagnose

2 Treat

Self-limiting infection Dogs that have likely resolved their infection 

Subclinical infection Infected dogs without any apparent signs of illness



Clinical disease Infected dogs with clinical signs that are recognizable

If necessary

3 Monitor

Retest in 1 year

4 Prevent

Discuss disease prevention strategies

Negative result Exposure unlikely

• Review benefits of prevention – preventives – vaccination • Retest in 1 year


STEPs—Simple Tools for Effective Protocols

Vector-borne Disease Screening

Protocol Implementation

page 2

Suggested Lyme Disease Screening Guidelines Transmitted by the deer tick or black-legged tick, Lyme disease is caused by the bacterium Borrelia burgdorferi. Clinical signs may not appear until several months after infection. Lyme disease has been found throughout North America with cases ranging from mild to severe. Did you know? The C6 peptide used in the IDEXX SNAP® 3Dx®, SNAP® 4Dx®/and Lyme Quant C6® tests do not cross-react with antibody response to commercially available Lyme vaccines.1 Ixodes ticks are known to be vectors for both Lyme disease and anaplasmosis.  ogs with seroreactivity to both B. burgdorferi and Anaplasma phagocytophilum D may have two times the risk of developing clinical illness than singularly infected dogs.2

do next?

Positive result Infection is likely

Negative result Infection is unlikely

Determine antibody level with the Lyme Quant C6 Test and evaluate for proteinuria (UPC)

Review benefits of tick prevention

Clinical signs and/or laboratory findings DO support Lyme disease (C6 antibody level ≥30 U/mL)

Clinical signs and/or laboratory findings DO NOT support Lyme disease (C6 antibody level <30 U/mL)

2 Treat

Doxycycline/tetracycline

Not generally recommended

3 Monitor

Retest C6 antibody level with or without UPC in 6 months to confirm treatment success

Monitor for clinical signs

1 Diagnose*

4 Prevent

Primary vector Ixodes spp. (deer tick or black-legged tick) Transmission 24–48 hours of tick attachment Pathogen Borrelia burgdorferi spirochete, which localizes in tissues of infected dogs

What to do with your result

? What to

Medical background

Discuss disease prevention strategies

Clinical presentation Lyme is a chronic infection with clinical signs that may present acutely: • Fever, anorexia, lethargy • Joint swelling • Polyarthritis • Shifting leg lameness • Rapidly progressive renal failure • Neurologic syndromes Laboratory abnormalities • Elevated (≥30 U/mL) C6 antibody level • Proteinuria

*Serology is typically used to diagnose Lyme disease. B. burgdorferi localizes to the tissues and is therefore rarely detectable in the blood by PCR.3

1. O’Connor TP, Esty KJ, Hanscom JL, Shields P, Philipp MT. Dogs vaccinated with common Lyme disease vaccines do not respond to IR6, the conserved immunodominant region of the VlsE surface protein of Borrelia burgdorferi. Clin Diagn Lab Immunol. 2004;11(3):458–462. 2. Beall MJ, Chandrashekar R, Eberts MD, et al. Serological and molecular prevalence of Borrelia burgdorferi, Anaplasma phagocytophilum, and Ehrlichia species in dogs from Minnesota. Vector-Borne Zoonotic Dis. 2008;8(4):455–464. 3. Straubinger RK. PCR-based quantification of Borrelia burgdorferi organisms in canine tissues over a 500-day postinfection period. J Clin Microbiol. 2000;38(6):2191–2199.


STEPs—Simple Tools for Effective Protocols

Vector-borne Disease Screening

Protocol Implementation

page 3

Suggested Canine Anaplasmosis Screening Guidelines Canine granulocytic anaplasmosis is caused by the bacterium Anaplasma phagocytophilum and is transmitted by the deer tick or black-legged tick. A. phagocytophilum is an obligate intracellular pathogen of neutrophils. Many mammalian species, including humans, are susceptible to infection. Did you know? Coinfection of Anaplasma species with other vector-transmitted pathogens may lead to more complex disease presentations and a slower response to therapy Anaplasma platys is the cause of infectious cyclic thrombocytopenia in dogs, and antibodies to this pathogen cross-react with the A. phagocytophilum spot on the SNAP 4Dx Test A. platys infects canine platelets and is frequently seen as a coinfection with Ehrlichia canis What to do with your result

? What to

do next?

1 Diagnose*

2 Treat

3 Monitor

4 Prevent

Positive result The dog has been exposed and may be infected

Negative result Exposure is unlikely

Check for hematologic abnormalities (CBC and/or blood film)

Review benefits of tick prevention

Clinical signs and/or laboratory findings DO support anaplasmosis

Clinical signs and/or laboratory findings DO NOT support anaplasmosis

Doxycycline/tetracycline

Not generally recommended

Evaluate platelet count in 1 week; if no improvement, pursue other diagnoses

Recheck CBC at wellness exams

Discuss disease prevention strategies

Medical background Primary vector Ixodes spp. (deer tick or black-legged tick) Transmission <24 hours of tick attachment Pathogen Anaplasma phagocytophilum infects canine neutrophils Clinical presentation Can present acutely: • Fever, anorexia, lethargy • Joint pain and swelling • Lameness • Neurologic signs Laboratory abnormalities • Thrombocytopenia • Lymphopenia • Increased liver enzymes

*Additional diagnostics may include PCR or Anaplasma IFA titer. See the Diagnostics for Sick Patients section of this guide for more information on serological and PCR testing.

Note Not known to be chronic, but experimental studies have shown persistent infection.4

4. Egenvall A, Lilliehöök I, Bjöersdorff A, Engvall EO, Karlstam E, Artursson K, Heldtander M, Gunnarsson A. Detection of granulocytic Ehrlichia species DNA by PCR in persistently infected dogs. Vet Rec. 2000;146(7):186–190.


STEPs—Simple Tools for Effective Protocols

Vector-borne Disease Screening

Protocol Implementation

page 4

Suggested Canine Ehrlichiosis Screening Guidelines Canine ehrlichiosis is caused by the bacterium Ehrlichia canis and is transmitted by the brown dog tick. The infection may progress to a subclinical phase, which can last days, months or years. Chronic infections, if left untreated, can lead to bone marrow dysfunction or renal disease. Did you know? Dogs coinfected with E. canis and A. platys were found to have more severe anemia and thrombocytopenia than dogs with either single infection.5 E. canis, and likely A. platys, are transmitted by the same vector, the brown dog tick. In a study of healthy dogs with antibodies to E. canis, 39% were thrombocytopenic.6

What to do with your result

? What to

do next?

1 Diagnose*

2 Treat

3 Monitor

4 Prevent

Positive result The dog has been exposed and may be infected

Negative result Exposure is unlikely

Check for hematologic abnormalities (CBC and/or blood film) and changes in serum proteins

Review benefits of tick prevention

Clinical signs and/or laboratory findings DO support ehrlichiosis

Clinical signs and/or laboratory findings DO NOT support ehrlichiosis

Doxycycline/tetracycline

Not generally recommended

Evaluate platelet count in 1 week; if no improvement, pursue other diagnoses

Recheck CBC at wellness exams

Discuss disease prevention strategies

Medical Background Primary vector Rhipicephalus sanguineus (brown dog tick) Transmission Time needed for transmission is unknown Pathogen Ehrlichia canis infects canine monocytes Clinical presentation Can present acutely: • Fever • Anorexia • Lethargy • Uveitis • Lymphadenomegaly • Bleeding disorders • CNS signs Has a chronic nature: • Weight loss • Bleeding disorders • Polyarthritis • Seizures • Multisystemic signs

*Additional diagnostics may include PCR or Ehrlichia IFA titer. See the Diagnostics for Sick Patients section of this guide for more information on serological and PCR testing.

5. Gaunt SD, Ramaswamy C, Beall M, Caterina K, Breitschwerdt E. Potentiation of thrombocytopenia and anemia in dogs experimentally coinfected with Anaplasma platys and Ehrlichia canis. JVIM. 2007;21(3):576. 6. Hegarty BC, Diniz PPVP, Bradley JM, Lorentzen L, Breitschwerdt EB. Clinical relevance of annual screening using a commercial enzyme-linked immunosorbent assay (SNAP 3Dx) for canine ehrlichiosis. JAAHA. 2009;45(3):118–124.

Laboratory abnormalities • Anemia • Thrombocytopenia • Hyperglobulinemia • Hypoalbuminemia • Pancytopenia • Proteinuria


STEPs—Simple Tools for Effective Protocols

Vector-borne Disease Screening

Protocol Implementation

page 5

Suggested Heartworm Screening Guidelines Dirofilaria immitis, the causative agent of heartworm disease, is transmitted by infected mosquitoes when D. immitis larvae are transferred to a healthy dog. Heartworm has no obvious clinical signs in the early stages, making preventative measures so much more important—especially as advanced infection may result in death. Did you know?

Medical background

 espite availability of monthly preventatives, prevalence rates of canine heartworm D has remained consistent nationwide.7

Primary vector Mosquitoes

The earliest heartworm antigen and microfilariae can be detected postinfection is 5 months and 6.5 months, respectively. For more information and current recommendations on treating canine heartworm disease, go to heartwormsociety.org or capcvet.org.

Pathogen Dirofilaria immitis

What to do with your result Canine heartworm testing

No clinical signs

HW Ag NEGATIVE

No action required

Follow-up Refer to the American Heartworm Society (AHS)/Companion Animal Parasite Council (CAPC) guidelines on chemoprophylaxis

Transmission Prepatent period approximately 6 months

Clinical signs

HW Ag POSITIVE

• Confirm with retest • Radiographs (assess cardiopulmonary disease) • CBC, chemistry and/or other appropriate tests

Treatment/Follow-up • Treat according to the American Heartworm Society guidelines • Retest 6 –12 months assessing for: -C  onversion to Ag negative status - Improvement of cardiopulmonary disease

HW Ag NEGATIVE

• Modified Knott’s testing for microfilariae* • Radiographs • CBC, chemistry and/or other appropriate tests • Consider other differential diagnoses If no definitive diagnosis, repeat in 1–3 months

Treatment/Follow-up Dependent upon supplementary test results *Less than 1% of infections will have microfilariae but not be antigenemic (American Heartworm Society)

© 2011 IDEXX Laboratories, Inc. All rights reserved. • 09-71486-00 • All ®/ TM marks are owned by IDEXX Laboratories, Inc. or its affiliates in the United States and/ or other countries. The IDEXX Privacy Policy is available at idexx.com.

Clinical presentation Asymptomatic at first, later developing: • Mild, persistent cough • Lethargy • Exercise intolerance • Reduced appetite • Weight loss

7. Verdon DR. Heartworm infection continues its climb, survey reports. DVM Newsmagazine. February 1, 2006.

Boli transmise prin vectori  

ghidul bolilor transmise prin vectori

Read more
Read more
Similar to
Popular now
Just for you