IDEXX Reference Laboratories

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IDEXX 4Dx Plus Test

The most trusted results in vector-borne disease screening.

  • The standard for detecting heartworm and tick-borne disease.
  • Available in-house as the SNAP 4Dx Plus Test or from IDEXX Reference Laboratories as the 4Dx Plus Screen.
  • Peer-reviewed studies support that the 4Dx Plus Test is the most accurate screening test available.1–3

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Icons of a mosquito and a tick

Screen for six vector-borne diseases

This ELISA detects heartworm antigen, Ehrlichia canis, Ehrlichia ewingii, Anaplasma phagocytophilum, Anaplasma platys, and Lyme antibodies (Borrelia burgdorferi infection) in a single blood specimen.

Available in-clinic or from IDEXX Reference Laboratories

SNAP 4Dx Plus Test

Reference-laboratory quality in the palm of your hand, for superior diagnostic accuracy at the point of care.

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The SNAP 4Dx Plus

4Dx Plus Screen

Available from IDEXX Reference Laboratories:
As a stand-alone test

4DX—4Dx Plus Screen—Canine

ELISAs for heartworm antigen, Ehrlichia canis, Ehrlichia ewingii, Anaplasma phagocytophilum, Anaplasma platys, and Lyme C6 antibodies

As part of a more complete parasite screen

VFI—Fecal Dx Antigen Panel with 4Dx Plus Screen—Canine

4Dx Plus Screen, hookworm, roundworm, and whipworm antigens by ELISA

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Superior performance for a higher level of confidence in results

Peer-reviewed studies1–3 show:

  • Consistently and accurately detects evidence of infection. 
  • Delivers significantly superior sensitivity and specificity. 
  • Produces positive results that can be trusted to be true positives.

Accuracy matters

The purpose of a vector-borne disease screening test is to detect evidence of infection. Veterinarians can trust that the 4Dx Plus Test accurately reflects disease status, for confident clinical decisions.

Graphic showing exposure to tick-borne disease increases risk of developing chronic kidney disease


Exposure to tick-borne disease increases risk of developing chronic kidney disease. 

Read the study.

Related products

Three screens showing the VetConnect PLUS application

View and trend all your results

Whether the IDEXX 4Dx Plus Test is run at IDEXX Reference Laboratories or in-clinic using a SNAP Pro Analyzer, you can review, interpret, and trend results right in VetConnect PLUS.

German shorthair pointer mix sitting on green grass

Get a more complete parasite screen

Every time you run a vector-borne disease screen, include Fecal Dx antigen testing for the detection of hookworm, roundworm, and whipworm infections.

Dog on woman's lap getting blood drawn by a veterinary technician

Get deeper insights with Lyme Quant C6

The Lyme Quant C6 Test measures the level of Cantibodies in your patient’s blood. Quickly identify Lyme infection in canine patients and monitor your treatment choices using valuable, measurable information. Contact us.


Directory of Tests and Services

Our unrelenting commitment to innovation keeps you at the forefront of diagnostic advancements and patient care with IDEXX-exclusive tests.

IDEXXCare Plus

Keeping your practice up-to-date and running smoothly is the IDEXXCare Plus promise. We’re at your service 24 hours a day, 7 days a week, to help you deliver the best veterinary care and customer experiences possible.

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  1. Goldstein RE, Eberts MD, Beall MJ, Thatcher B, Chandrashekar R, Alleman AR. Performance comparison of SNAP 4Dx Plus and AccuPlex4 for the detection of antibodies to Borrelia burgdorferi and Anaplasma phagocytophilum. Intern J Appl Res Vet Med. 2014;12(2):141–147.
  2. Eberts MD. Performance of SNAP 4Dx Plus and AccuPlex4 in dogs with different heartworm burdens. Intern J Appl Res Vet Med. 2013;11(1):7–9.
  3. Liu J, Drexel J, Andrews B, Eberts M, Breitschwerdt E, Chandrashekar R. Comparative evaluation of 2 in-clinic assays for vector-borne disease testing in dogs. Top Companion Anim Med. 2018;33(4):114–118.