Rabies- No Way For A Friend To Die

by Tanja Winkler, DVM

               Rabies is a viral disease which attacks the central nervous system of its victims. Currently there is no treatment for rabies- infected horses always die!!! The rabies reservoir in the environment is maintained by certain key species- skunks, foxes, raccoons, & bats. Horses are one of the most susceptible species, and often come into contact with the reservoir species. The number of rabies cases in both wildlife and domestic animals has increased over the last 20 years, with annual reported cases generally exceeding 9,000.

Rabid animals have high concentrations of the virus in their saliva. Horses usually become infected through bite wounds on their lower limbs or muzzles, which often go unnoticed. The virus can also enter the body through fresh open cuts in the skin or mucous membranes such as the eyes, mouth, or nose. The incubation time between when the virus enters the body and the onset of clinical signs averages two to nine weeks, but may be as long as fifteen months. Death usually occurs three to five days after the onset of clinical signs and sometimes in less than one day.

               Equine Rabies “can look like anything”. Colic, lameness, ataxia (incoordination), paralysis, urinary incontinence, muscle tremors, fever, depression, aggressiveness, hyperesthesia (increased sensitivity to touch or stimulus), and convulsions are some of the most commonly reported signs. Because of the many different clinical presentations, rabies is often initially misdiagnosed. This can place owners and veterinarians at serious risk of exposure. This is where my own personal soap-box comes into play. During my clinical year in vet school, 20 students, including myself, were exposed to rabies through a pony, which had been referred into the hospital. We were all required to undergo post-exposure treatment which was both costly and made some of us rather sick.

               This past fall, approximately 150,000 people were potentially exposed to rabies when they attended the Tennessee Walking Horse National Celebration in Shelbyville, Tennessee, where a 3-yr-old gelding who was being shown was diagnosed after being euthanized for neurologic disease. The Tennessee Department of Health and the CDC had to contact everyone potentially exposed to assess their risk.

               Rabies poses a serious public health risk, as well as the threat of a miserable death for the individual infected. Currently there is no successful treatment for rabies. If an unvaccinated horse is potentially exposed to rabies, authorities will recommend that it be euthanized and have its brain sent in for testing. The only other option is a strict 6 month quarantine under observation for clinical signs. Rabies infection can easily be prevented through routine vaccination. Please contact TEC to see if your horse is up to date on his vaccines.