STEPs—Simple Tools for Effective Protocols

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.

If necessary

Retest in 1 year

Discuss disease prevention strategies

Depending on the results of your pet’s wellness screening, additional testing or therapies may be required.

Your pet’s screening result and what it means

•Reviewbenefits of prevention – preventives – vaccination

•Retestin1year

Negative result Exposure unlikely

Positive result The dog has been exposed and may be infected

Runadditionalteststoconfirminfection

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

Clinicalsignsand/orlaboratoryfindingsindicateeither

Monitor

Prevent

Treat

Diagnose

What to do next?

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Medical background

Primary vectorIxodes spp. (deer tick or black-legged tick)

Transmission24–48 hours of tick attachment

PathogenBorrelia burgdorferi spirochete, which localizes in tissues of infected dogs

Clinical presentationLyme is a chronic infection with clinical signs that may present acutely:• Fever,anorexia,lethargy• Jointswelling• Polyarthritis• Shiftingleglameness• Rapidlyprogressiverenalfailure• Neurologicsyndromes

Laboratory abnormalities• Elevated(≥30 U/mL) C6

antibody level• Proteinuria

Suggested Lyme Disease Screening Guidelines

Reviewbenefits of tick prevention

Doxycycline/tetracycline

Monitor for clinical signs

Retest C6 antibody level with or without UPC in 6monthstoconfirmtreatment success

Monitor

Prevent Discuss disease prevention strategies

Not generally recommendedTreat

Clinical signs and/or laboratoryfindingsDO NOT

support Lyme disease (C6 antibody level <30 U/mL)

Clinical signs and/or laboratoryfindingsDO

support Lyme disease (C6 antibody level ≥30 U/mL)

Diagnose*

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

What to do next?

What to do with your result

Negative result Infection is unlikely

Positive result Infection is likely

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.

Dogs with seroreactivity to both B. burgdorferi and Anaplasma phagocytophilum may have two times the risk of developing clinical illness than singularly infected dogs.2

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* 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’ConnorTP,EstyKJ,HanscomJL,ShieldsP,PhilippMT.Dogsvaccinated 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.BeallMJ,ChandrashekarR,EbertsMD,etal.Serologicalandmolecularprevalence of Borrelia burgdorferi, Anaplasma phagocytophilum, and Ehrlichia species in dogs from Minnesota. Vector-Borne Zoonotic Dis. 2008;8(4):455–464.

3.StraubingerRK.PCR-basedquantificationofBorreliaburgdorferiorganismsincaninetissuesovera500-daypostinfectionperiod.JClinMicrobiol. 2000;38(6):2191–2199.

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Monitor

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Treat

Diagnose*

What to do next?

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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

Medical background

Primary vectorIxodes spp. (deer tick or black-legged tick)

Transmission<24 hours of tick attachment

PathogenAnaplasma phagocytophilum infects canine neutrophils

Clinical presentationCan present acutely:• Fever,anorexia, lethargy• Jointpainandswelling• Lameness• Neurologicsigns

Laboratory abnormalities• Thrombocytopenia• Lymphopenia• Increasedliverenzymes

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

Suggested Canine Anaplasmosis Screening Guidelines

Reviewbenefits of tick prevention

Checkforhematologicabnormalities(CBCand/orbloodfilm)

Positive result The dog has been exposed and may be infected

Negative result Exposure is unlikely

What to do with your result

Discuss disease prevention strategies

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

other diagnoses

Recheck CBC at wellness exams

Not generally recommendedDoxycycline/tetracycline

Clinical signs and/orlaboratoryfindingsDO NOT support

anaplasmosis

Clinical signs and/orlaboratoryfindings

DO support anaplasmosis

* Additional diagnostics may include PCR or Anaplasma IFAtiter.SeetheDiagnosticsfor Sick Patients section of this guide for more information on serological and PCR testing.

4. Egenvall A, Lilliehöök I, Bjöersdorff A, Engvall EO, Karlstam E,ArturssonK,HeldtanderM,GunnarssonA.Detectionofgranulocytic Ehrlichia species DNA by PCR in persistently infected dogs. Vet Rec. 2000;146(7):186–190.

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Monitor

Prevent

Treat

Diagnose*

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Medical background

Primary vectorRhipicephalus sanguineus (brown dog tick)

TransmissionTime needed for transmission is unknown

PathogenEhrlichia canis infects canine monocytes

Clinical presentationCan present acutely:• Fever• Anorexia• Lethargy• Uveitis• Lymphadenomegaly• Bleedingdisorders• CNSsigns

Hasachronicnature:• Weightloss• Bleedingdisorders• Polyarthritis• Seizures• Multisystemicsigns

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

Suggested Canine Ehrlichiosis Screening Guidelines

Reviewbenefits of tick prevention

Check for hematologic abnormalities (CBC and/or bloodfilm)andchangesinserumproteins

Positive result The dog has been exposed and may be infected

Negative result Exposure is unlikely

What to do with your result

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

Recheck CBC at wellness exams

Not generally recommendedDoxycycline/tetracycline

Clinical signs and/or laboratoryfindingsDO NOT support

ehrlichiosis

Clinical signs and/orlaboratoryfindings

DO support ehrlichiosis

Discuss disease prevention strategies

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

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

other diagnoses

5.GauntSD,RamaswamyC,BeallM,CaterinaK,BreitschwerdtE.PotentiationofthrombocytopeniaandanemiaindogsexperimentallycoinfectedwithAnaplasmaplatysandEhrlichiacanis.JVIM.2007;21(3):576.

6.HegartyBC,DinizPPVP,BradleyJM,LorentzenL,BreitschwerdtEB.Clinicalrelevanceofannualscreeningusingacommercialenzyme-linkedimmunosorbentassay(SNAP3Dx)forcanineehrlichiosis.JAAHA.2009;45(3):118–124.

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Treatment/Follow-upDependent upon supplementary test results

Treatment/Follow-up•TreataccordingtotheAmerican

HeartwormSocietyguidelines•Retest6–12monthsassessingfor:

- Conversion to Ag negative status - Improvement of cardiopulmonary

disease

Follow-upRefer to the American HeartwormSociety(AHS)/CompanionAnimal Parasite Council (CAPC) guidelines on chemoprophylaxis

* Less than 1% of infections willhavemicrofilariaebutnotbe antigenemic (American HeartwormSociety)

•ModifiedKnott’stesting formicrofilariae*

•Radiographs•CBC,chemistryand/or

other appropriate tests•Considerother

differential diagnosesIfnodefinitivediagnosis,repeat in 1–3 months

No action required

HWAgNegATiVe

•Confirmwithretest•Radiographs(assess

cardiopulmonary disease)•CBC,chemistryand/orother

appropriate tests

HWAgPoSiTiVe HWAgNegATiVe

No clinical signs Clinical signs

Canine heartworm testing

Medical background

Primary vector Mosquitoes

TransmissionPrepatent period approximately 6 months

PathogenDirofilaria immitis

Clinical presentationAsymptomaticatfirst,laterdeveloping:• Mild,persistentcough• Lethargy• Exerciseintolerance• Reducedappetite• Weightloss

Suggested Heartworm Screening Guidelines

What to do with your result

Dirofilaria immitis, the causative agent of heartworm disease, is transmitted by infected mosquitoes when D. immitis larvae are transferred to a healthy dog. Heartwormhasnoobviousclinicalsignsintheearlystages,makingpreventativemeasures so much more important—especially as advanced infection may result in death.

Did you know?

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

Theearliestheartwormantigenandmicrofilariaecanbedetectedpostinfectionis 5 months and 6.5 months, respectively.

Formoreinformationandcurrentrecommendationsontreatingcanine heartworm disease, go to heartwormsociety.org or capcvet.org.

©2011IDEXXLaboratories,Inc.Allrightsreserved.•09-71486-00•All®/TMmarksareownedbyIDEXXLaboratories,Inc.oritsaffiliatesintheUnitedStatesand/or other countries. The IDEXX Privacy Policy is available at idexx.com.

7.VerdonDR.Heartworminfectioncontinuesitsclimb,surveyreports.DVMNewsmagazine.February1,2006.

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