IDEXX Laboratories Responds to EHV-1 Multistate Outbreak
May 19, 2011
Reports of an equine herpesvirus myeloencephalopathy (EHM) outbreak caused by the neuropathogenic form of equine herpesvirus type 1 (EHV-1) have surfaced within the past 5 days. Cases have been reported in several U.S. states and in Canada. While the true extent of this disease outbreak is still uncertain, there is a significantly increased risk of EHM cases at this time. Control of the outbreak is critically dependent on biosecurity. Part of the biosecurity measure is to accurately identify infected horses in a timely manner using the appropriate diagnostic tests.
Diagnostic options
Real-time PCR has become the diagnostic test of choice because of its high analytical sensitivity and specificity. Virus isolation, another available methodology, is time-consuming and less sensitive than real-time PCR. IDEXX offers a range of RealPCR™ testing options for identification of horses infected with EHV-1.
Horse populations recommended for testing
- Sick or healthy horses exposed to EHM confirmed horses.
- Horses with neurological signs of EHM, including high fever, ataxia, partial or complete paralysis and incontinence.
- Horses that are quarantined until EHV-1 infection is confirmed or eliminated based upon both a negative PCR test and a lack of clinical signs for the disease.
IDEXX RealPCR tests and panels
| when to use | test name and contents | test code |
|---|---|---|
| Screening of nonclinical or clinical, exposed horses | Equine Herpesvirus Types 1 and 4 RealPCR™ Tests 2–11 samples 12 or more samples | 2699 26992 26993 |
| Horses with neurological clinical signs compatible with EHM | Equine Neurologic Disease Panel EPM by Western blot, West Nile virus IgM antibody by capture ELISA, equine herpesvirus type 1 (EHV-1) RealPCR™ test | 2619 |
| Comprehensive respiratory screening of clinical horses with unknown exposure history | Equine Respiratory RealPCR™ Panel Equine influenza virus (EIV/H3N8), equine herpesvirus type 1 (EHV-1) and type 4 (EHV-4) and Streptococcus equi RealPCR™ tests; includes culture and biochemical identification of S. equi. | 2740 |
| Treatment monitoring of EHV-1 confirmed horses | Equine Herpesvirus Type 1 RealPCR™ Test 2–11 samples 12 or more samples | 2566 25662 25663 |
Specimen requirements
7 mL EDTA whole blood or nasal swabs (one from each nostril). For equine neurologic disease panel submissions, include 2 mL of serum. For respiratory disease panel submissions, nasal swabs are preferred sample type and should be collected prior to antibiotic administration. For nasal swabs, please submit dry, plastic-stemmed swabs, without transport media, in a plain serum tube or an empty, sterile tube; keep refrigerated.
Contacting IDEXX
If you have any questions regarding IDEXX RealPCR tests and panels as well as the EHV-1 outbreak, including disease management, biosecurity, vaccination or treatment options, please do not hesitate to call the IDEXX equine internal medicine consulting service at 1-888-433-9987, option 4, then option 3. Because of the large volume of testing, there may be some minor delays in reference laboratory test results.
IDEXX complies with local and national reporting requirements for EHV.