AUGUSTA — The first horse in Maine to test positive for Eastern equine encephalitis in four years had to be euthanized last weekend.
Dr. Michele Walsh, the state veterinarian, confirmed Wednesday that the horse, which was stabled at a property in Oxford County, tested positive after displaying symptoms from the disease that is transmitted through the bite of an infected mosquito.
Walsh declined to identify the town in Oxford County where the horse lived. It is the first reported case of EEE in Oxford County.
Eight pools of mosquitoes have tested positive for EEE in York County this year. Maine last saw EEE in horses in 2009 when 15 horses died of the disease.
“We think it’s important for Oxford County residents to realize that mosquitoes pay no mind to county boundaries,” she said.
Walsh said the best protection against EEE is to make sure that a horse receives a booster dose every six months, and if possible, just before mosquito season begins in May.
The horse that died was vaccinated for EEE and West Nile virus about a year ago, but had not been given a booster dose, Walsh said.
“EEE , which is carried by mosquitoes, is a fatal, viral disease in horses. The virus can affect human beings if they are bitten by mosquitoes that carry the virus,” Walsh said in a statement that was issued Wednesday. “People cannot acquire EEE infection from sick animals, only from the bite of an infected mosquito.”
Walsh said the horse’s owner contacted a local veterinarian last week after the animal began falling asleep on its feet, was unsteady when it walked, and seemed to have trouble seeing.
Other symptoms of EEE in an horse may include: head pressing, tremors, circling and seizures.
EEE has been known to infect llamas, alpacas and emus, ostriches and other farm birds, such as quail and ducks.
A flock of pheasants in the town of Lebanon tested positive for EEE last year, according to Walsh.
Walsh said she is not surprised that EEE infected a horse in Maine. Massachusetts has confirmed at least two cases of EEE in horses this year.
“We expected to see some level of infection in Maine so this is not a shock. The good news is we are at the end of mosquito season,” Walsh said.
Dr. Sheila Pinette, director of the Maine Center for Disease Control, said the EEE in horses should serve as a reminder that people are at risk too.
Staff Writer Dennis Hoey can be contacted at 791-6365 or at: