Oregon State University’s veterinary hospital resumed normal operations Nov. 29, ending a three-week quarantine instituted as it treated a horse with a contagious and potentially deadly neurotropic illness.
Erica McKenzie, professor of large animal internal medicine at OSU’s College of Veterinary Medicine, said no other horses got sick during the quarantine period. “The college thanks everyone for their patience and assistance during the quarantine period,” McKenzie said in a news release. The horse recovered and was taken home.
The horse became severely ill Nov. 4 at its owner’s property in Coos Bay, Ore., and was taken to OSU’s Lois Bates Acheson Veterinary Teaching Hospital for treatment.
The horse developed a mutated form of Equine Herpes Virus-1, or EHV-1, which is a common sickness in horses. It usually causes minor respiratory problems and is something like a cold is to humans, but in its mutated form the virus attacks the nervous system.
The illness often first shows up as weakness in the hind quarters, with animals stumbling or developing an unusual gait. Other signs include weak tail tone, nasal discharge, fever, and difficulty urinating. Geldings and stallions may be unable to retract their penis. Pregnant mares may abort. In rare cases, EHV-1 can cause blindness and central nervous system damage in alpacas and llamas.
Because the virus is contagious, OSU suspended elective procedures on horses, alpacas and llamas. The virus doesn’t harm humans, but people can spread it to animals after picking it up by hand or clothing contact with sick horses.
A vaccine for EHV-1 can ease symptoms of the common form of the virus, but it does not prevent animals from developing the more serious nervous system illness.
More information about EHV-1 and biosecurity recommendations are available from the American Association of Equine Practitioners at https://aaep.org/guidelines/infectious-disease-control/equine-herpesvirus-resources.