11/21/2025
‼️ Important Information Regarding Equine Herpesvirus 1 (EHV 1) ‼️
As of this morning’s Equine Disease Communication Center (EDCC) report, 8 horses who have attended competitive speed events in the Oklahoma and Texas region have tested positive for the neurologic strain of Equine Herpesvirus 1. Our infectious disease team is closely monitoring the situation and is watching for any horses in Indiana that may have been exposed to or are showing signs of any form of Equine Herpesvirus infection.
⚠️ About the virus: ⚠️
There are five common strains of Equine Herpesvirus, and EHV 1 is the most concerning. It is the strain involved in the current outbreak because it can cause respiratory disease, neurologic disease known as Equine Herpes Myeloencephalitis, and reproductive disease. Vaccination reduces the amount of virus shed by infected horses but does not prevent the neurologic form.
Clinical signs to watch for:
☑️ Fever greater than 101.5 F
☑️ Lethargy or decreased appetite
☑️ Nasal discharge
☑️ Weakness
☑️ Hind end incoordination
☑️ Urine dribbling or incontinence
☑️ Abortion or miscarriage in pregnant mares
Contact your veterinarian immediately if you notice any of these signs.
⚠️ Should you continue showing or hauling? ⚠️
The safest option is to avoid unnecessary travel until we better understand the extent of the outbreak. As of November 19, there are no confirmed or suspected cases of EHV 1 or EHM in Indiana. For horses that must travel, minimize contact, choose well-ventilated stabling, avoid overnight stabling if possible, ensure vaccinations are current, take your horse’s temperature morning and evening, and record these values for at least five days after returning home.
🧪 Testing information: 🧪
Horses without fever and without known exposure are very unlikely to test positive.
If your horse has a fever, your veterinarian will collect a nasal swab and a blood sample to test for virus in nasal secretions and circulating white blood cells.
🐎At Purdue we offer:
✅ The full blood and nasal swab gold standard test through the ADDL
✅ A one-hour Fluxergy nasal swab screening test for horses with fever or nasal discharge
Horses from high-risk events or horses with fever may be asked to wait in the trailer or at the isolation facility while we process the one-hour screening test to help keep all patients safe.
☎️ For questions or suspected cases, contact the Purdue University Equine Hospital at 765 496 8548.
📞 For testing, contact the Indiana Animal Disease Diagnostic Laboratory at 765-494-7440.
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