Maine state veterinary officials are reminding owners that now is the time vaccinate horses to help protect them from rabies and mosquito-borne diseases such as Eastern equine encephalitis (EEE) and West Nile virus (WNV).

Vaccinating horses annually against rabies, EEE, and WNV is one of the most important ways to protect them from these dangerous diseases, which can cause neurologic signs and lead to death, especially in unvaccinated animals. Maine Department of Agriculture, Conservation, and Forestry officials are cautioning against complacency; even though there were no cases of rabies, EEE, or WNV in Maine horses last year, annual vaccination is safe, effective, and essential to maintain protection against these potentially deadly infections, they say.

Rabies—a zoonotic disease that can be spread from animals to humans—is caused by a lyssavirus that affects the neurologic system and salivary glands. Horses are exposed most commonly through the bite of another rabid animal.

In horses rabies’ clinical signs 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 aggression. Once clinical signs appear, there are no treatment