DHEC: Cases of Eastern Equine Encephalitis in Horses present in SC

State Health officials say Eastern Equine Encephalitis has been detected in 11 horses in 8 SC counties

COLUMBIA, SC (WOLO)– State Health officials say Eastern Equine Encephalitis has been detected in 11 horses in 8 South Carolina counties.

The disease is a mosquito-borne illness.

DHEC says the virus was detected in the Lowcountry, Midlands, and Pee Dee from July 10 to August 21, 2020. The counties where the virus has been found, include Aiken, Berkeley, Colleton, Florence, Horry, Jasper, Lexington, and Marion.

DHEC says the EEE virus takes two to five days to cause symptoms in horses and has a 90 percent fatality rate. The virus causes stumbling and poor coordination, inability to rise, paralysis, head pressing, circling and convulsions.

Health officials say Veterinarians frequently recommend vaccination before likely exposure to mosquito bites and booster vaccinations to ensure appropriate immunity levels in horses.

DHEC says, in people, EEE virus takes roughly three to 10 days to cause symptoms. The virus initially causes fever, malaise, intense headache, muscle aches, nausea and vomiting. Neurologic signs of EEE, which may appear within 5 days of infection, include meningitis, encephalitis, seizures and coma.

Ninety-six percent of people infected with EEE virus do not develop symptoms, however, of those who do, one-third or more die, and the others frequently suffer permanent and severe neurologic damage, say health officials.

Experts say people can protect themselves from mosquito bites by:

• Using an EPA-registered repellent containing catnip or catmint oil (nepetalactone), oil of citronella, DEET, IR 3535, oil of lemon eucalyptus (OLE or PMD), picaridin or 2-undecanone. Oil of lemon eucalyptus should not be used on children younger than three years old. Repellents containing 30% or more of the active ingredient DEET do not significantly increase protection.
• Avoiding the outdoors at dawn or dusk when mosquitoes are most active.
• Wearing long sleeves and pants.
• Keeping property clear of standing water in which mosquitoes can breed.

“The risk for EEE and West Nile virus transmission to people is always greater toward the end of mosquito season, even after extended periods of cold weather”, said Dr. Chris Evans, State Public Health Entomologist with DHEC’s Bureau of Environmental Health Services.