Respiratory symptoms got you breathless? Try our equine respiratory PCR panel -- we test for 7 respiratory bacteria and viruses from 1 swab.

Neurological symptoms got you down? Try our equine neurological PCR panel -- we test for 5 neurological diseases from 1 CSF or tissue sample.

Diarrhea got you on the run? Try our equine GI / diarrhea PCR panel -- we test for 4 GI diseases from 1 fecal or swab sample.

Oh baby! Our equine breeding/abortion PCR panel tests for 5 diseases affecting breeding success from 1 swab or semen sample.

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For our international clients: Our DRY CARDS let you mail blood samples to Zoologix easily and cheaply from anywhere. Samples are small, light and stable at room temperature.

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Zoologix performs equine PCR tests for...

African horse sickness

Anaplasma phagocytophilum





Borna virus

Borrelia burgdorferi

Burkholderia mallei and pseudomallei

Clostridium difficile

Clostridium species

Contagious equine metritis (CEM)




Eastern equine encephalitis (EEE)

E. coli O157:H7

E. coli panel

Equine adenoviruses

Equine arteritis virus (EAV)

Equine hepatitis virus

Equine herpesvirus
type 1

Equine herpesvirus
type 2

Equine herpesvirus
type 3

Equine herpesvirus
type 4

Equine herpesvirus
type 5

Equine infectious anemia (EIA)

Equine parvovirus

Equine piroplasmosis

Equine protozoal myeloencephalitis (EPM)





Horsepox virus

Influenza type A

Japanese encephalitis

Lawsonia intracellularis


Lyme disease


Neospora caninum

Neospora hughesi


Potomac horse fever


Rhodococcus equi


Sarcocystis neurona

St. Louis encephalitis

Strangles (Strep equi)

Streptococcus pneumoniae




Taylorella equigenitalis

Theileria equi

Toxoplasma gondii


Trypanosoma equiperdum

Trypanosoma evansi

Venezuelan equine encephalitis (VEE)

Vesicular stomatitis

West Nile virus (WNV)

Western Equine Encephalitis (WEE)

Yersinia enterocolitica

Yersinia pseudotuberculosis

Genetic tests for...

Hyperkalemic periodic paralysis

Equine herpes 4 PCR test
equine assay data sheet

Equine herpesvirus type IV (EHV-4)

Test code:
S0074 - Ultrasensitive qualitative detection of equine herpesvirus type IV by real time polymerase chain reaction.

S0074 is included in P0013 - equine respiratory panel


Equine herpesvirus I (EHV-1) and EHV-4 comprise two genetically and antigenically distinct groups of viruses that can cause viral rhinopneumonitis in horses. Both viruses are ubiquitous in horse populations worldwide. Each produces an acute febrile respiratory disease on primary infection, characterized by rhinopharyngitis and tracheobronchitis. Outbreaks of respiratory disease occur annually among foals in areas with concentrated horse populations; elsewhere, episodes are sporadic. Most of these outbreaks in weanlings are caused by strains of EHV-4. The age, seasonal, and geographic distributions vary and probably are determined by immune status and concentration of horses. In individual horses, the outcome of exposure is determined by viral strain involved, immune status, pregnancy status, and possibly age. Infection of pregnant mares with EHV-4 strains rarely results in abortion.

The mechanisms of EHV-1 and EHV-4 infections are significantly different. EHV-4 infections are restricted to respiratory tract epithelium and associated lymph nodes, while EHV-1 strains have a predilection for vascular endothelium, especially in the nasal mucosa, lungs, adrenal, thyroid, and CNS. Of additional significance is the leukocyte-associated viremia that occurs in EHV-1 infections, which may result in abortion or neurologic disease.

Equine viral rhinopneumonitis cannot be clinically differentiated from equine influenza, equine viral arteritis, or certain other equine respiratory infections solely on the basis of clinical signs. Confirmation can be achieved by virus isolation, preferably from nasopharyngeal swabs and citrated blood samples taken very early in the course of the infection and by serologic testing of acute and convalescent sera. However, culture identification of the virus is slow and not very sensitive. Serological testing requires 3 to 4 weeks to complete. Molecular detection by PCR is the most sensitive and specific method of identifying EHV-4 infection (Varrasso et al., 2001).


  • Help confirm the disease causing agent
  • Shorten the time required to confirm a clinical diagnosis of EHV-4 infection
  • Help ensure that horse populations are free of EHV-4
  • Early prevention of spread of this virus
  • Minimize personnel exposure to this virus
  • Safety monitoring of biological products that derive from horses

Varrasso, A., Dynon, K., Ficorilli, N., Hartley, C.A., Studdert, M.J. and Drummer, H.E. (2001) Identification of equine herpesviruses 1 and 4 by polymerase chain reaction. Aust. Vet. J. 79:563-569.

Specimen requirements: Nasopharyngeal swab, or 0.2 ml whole blood in EDTA (purple top) tube, or 0.2 ml fresh, frozen or fixed tissue, or cellular suspensions (platelets, PBMCs, etc).

Contact Zoologix if advice is needed to determine an appropriate specimen type for a specific diagnostic application. For specimen types not listed here, please contact Zoologix to confirm specimen acceptability and shipping instructions.

For all specimen types, if there will be a delay in shipping, or during very warm weather, refrigerate specimens until shipped and ship with a cold pack unless more stringent shipping requirements are specified. Frozen specimens should be shipped so as to remain frozen in transit. See shipping instructions for more information.

Turnaround time: 2 business days

Methodology: Qualitative real time PCR

Normal range: Nondetected

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