Rabies Confirmed in Two Middle Tennessee Horses

Thehorse.com

by: Edited Press Release
February 29 2012, Article # 19665


The Tennessee Departments of Health and Agriculture have confirmed rabies in two horses recently deceased horses. One horse, submitted for testing in January 2012, died in rural Rutherford County, and the other was submitted this month from Marshall County. Both horses had a type of rabies virus found in skunks in Tennessee, although it is not known how they were infected.

“The deaths of these animals serve as a somber reminder of the importance of rabies vaccination," said Health Commissioner John Dreyzehner, MD, MPH. "Our pets--often including horses--are more likely to come into contact with wild animals than people are. Protecting pets with rabies vaccination can provide a barrier against rabies from wild animals."

Rabies is caused by a lyssavirus affecting the neurological system and salivary glands. Exposure to horses most commonly occurs through the bite of another infected (rabid) animal, typically a raccoon, skunk, bat, or fox. Clinical signs of rabies in horses are variable and can take up to 12 weeks to appear after the initial infection. Although affected horses are sometimes asymptomatic, an infected horse can show behavioral changes, such as drowsiness, depression, fear, or aggressiveness. Once clinical signs appear, there are no treatment options.

Rabies can only be diagnosed post-mortem by submitting the horse's head to a local public health laboratory to identify the rabies virus using a test called fluorescence antibody. Therefore, ensuring that all other potential diseases have been ruled out is very important in these cases.

Commercially-available rabies vaccines are safe and extremely effective. According to the American Association of Equine Practitioners' (AAEP) vaccination guidelines, adult horses should be vaccinated annually and mares in foal should be vaccinated four to six weeks pre-partum or before breeding. Foals and weanlings less than 12 months of age are administered an initial series of three vaccines. The timing is dependent on the vaccination status of the mare. Thereafter, horses are vaccinated annually.

While rabies is relatively rare in horses--usually fewer than 100 horses are infected in the United States every year--it is an important disease because it is zoonotic. That is, it can be spread to humans. Further, rabies is a reportable disease and the proper authorities should be notified in the event a horse--or any other animal--tests positive.

For questions about animal health, contact the Tennessee Department of Agriculture at 615/837-5120 or animal.health@tn.gov.