A Virginia horse has tested positive for rabies, according to a report from the Martinsville Bulletin. Citing a Virginia Department of Health news release, the report indicated the affected horse resided in Patrick County, located near the North Carolina state line.

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 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 Practitioner’s 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