COLUMBIA, SC (WMBF) – A case of Eastern Equine Encephalitis (EEE) was discovered in a Dillon County horse last Friday, and now state veterinary officials are urging South Carolina horse owners to vaccinate their animals.
This was the first case of EEE discovered this year in South Carolina, according to a news release from Clemson University. EEE is a serious, mosquito-borne illness in horses that can also affect humans. It is almost always fatal in unvaccinated horses, killing 90 percent of exposed, unvaccinated horses. The horse in Dillon did not survive.
Symptoms of the disease usually develop in horses within two to five days after exposure, and include stumbling, circling, head-pressing, depression or apprehension, weakness of legs, partial paralysis, inability to stand, muscle twitching or death, the release states.
A simple vaccine will minimize the risk to horses and other equine species, the release continues.
"It can get out of hand if we don't vaccinate horses and control mosquitoes," said Boyd Parr, state veterinarian and director of Clemson University Livestock-Poultry Health. "The best defense for horse owners is to maintain current equine vaccinations for Eastern Equine Encephalitis, West Nile virus and rabies for their horses."
In 2013, South Carolina led the nation in cases of EEE, with 49 infected horses, Clemson officials stated. Of those, all but one died.
After that outbreak, due to increased vaccinations, there were only seven cases of EEE in 2014 and six in 2015. There was another spike in cases last year, with 15 infected horses.
The release explains how the disease is transmitted: "The EEE virus is maintained in nature through a cycle involving the freshwater swamp mosquito, Culiseta melanura, commonly known as the blacktailed mosquito. Two to three days after becoming infected with the virus a mosquito becomes capable of transmitting it. Infected mosquitoes can transmit the disease when they bite horses and humans."
EEE is a rare illness in humans, and most infected persons have no apparent illness, the release states. Severe cases begin with a sudden headache, high fever, chills and vomiting.
According to the Centers for Disease Control and Prevention, Eastern Equine Encephalitis is a rare illness in humans. Most persons infected with it have no apparent illness. Severe cases begin with the sudden onset of headache, high fever, chills and vomiting. People who are concerned should contact their physicians, Parr said.
The release concludes:
Rains at crucial times across much of South Carolina made conditions favorable for mosquito breeding again this year, Parr said.
Any livestock, including horses, that display neurologic signs, such as stumbling, circling, head-pressing, depression or apprehension, must be reported to the state veterinarian at 803-788-2260 within 48 hours, according to state law.
Information on animal diseases and reporting requirements can be found on the Livestock-Poultry Health website, www.clemson.edu/lph.