
Arizona Department of Agriculture has reported a case of respiratory equine herpesvirus (EHV) in Maricopa County. The infected horse resides at a private facility where 32 other horses have been exposed.
EDCC Health Watch, a program by Equine Network, uses information from the Equine Disease Communication Center (EDCC) to share verified equine disease reports. The EDCC is a nonprofit organization supported by industry donations to provide accessible infectious disease information.
Understanding EHV
Herpesvirus is highly contagious in horses and can lead to various conditions like rhinopneumonitis, abortion in broodmares, and equine herpesvirus myeloencephalopathy (EHM).
EHV-1 infection in horses can manifest as fever, cough, decreased appetite, depression, and nasal discharge. Pregnant mares may not show signs before aborting, which typically happens late in gestation. EHM presents with fever, respiratory symptoms, and neurologic signs like ataxia and weakness.
The virus spreads through close contact, contaminated equipment, and shared items. Biosecurity measures such as hygiene and disinfection play a crucial role in preventing disease transmission.
Vaccines may reduce viral shedding but do not protect against the neurologic form of EHV-1. Emphasizing biosecurity practices and disease prevention is key in controlling the spread of the virus.

