TALLAHASSEE – Florida Agriculture and Consumer Services Commissioner Charles Bronson is urging horse owners to get their animals vaccinated following an upsurge in the number of Eastern Equine Encephalitis cases. Sentinel chickens that serve as an early warning of the existence of the disease are also being diagnosed with EEE in areas of the state that are not usually affected.
So far this year there have been 16 confirmed cases of EEE in horses. While that is not an unusually high number, seven of the cases were all reported on Wednesday, June 23 from counties scattered throughout the state.

“Most of the cases have been in the central and north central part of the state which is normal,” Bronson said. “But we are also seeing increased EEE and WNV activity in sentinel chickens in the southern part of the state, including Martin County which has not had EEE detected in 30 years. In addition, there has been a confirmed case of EEE in a horse in both Collier and Okeechobee Counties. So I want to remind horse owners of the importance of getting their animals vaccinated.”

EEE is a viral disease that affects the central nervous system and is transmitted to horses by infected mosquitoes. Signs of the virus include fever, listlessness, stumbling, circling, coma and usually death. The disease is fatal in horses in 90 percent of the cases. Bronson says the majority of cases of EEE and other mosquito borne diseases can be prevented through proper vaccinations. Horse owners are urged to check with their veterinarian to make sure their animals have received current vaccinations and booster shots against EEE and West Nile Virus, and that these shots are kept up to date.
There are ongoing efforts to keep the mosquito populations down but because there is no fool-proof method to prevent the diseases, vaccinations are critical.
In addition to infecting horses, equine encephalitis affects humans. Eastern equine encephalitis also infects birds that live in freshwater swamps of the eastern U.S. seaboard and along the Gulf Coast. In humans, symptoms are seen 4-10 days following transmission and include sudden fever, general flu-like muscle pains, and headache of increasing severity, followed by coma and death in severe cases. About half of infected patients die from the disorder. Fewer than 10 human cases are seen annually in the United States. Western equine encephalitis is seen in farming areas in the western and central plains states. Symptoms begin 5-10 days following infection. Children, particularly those under 12 months of age, are affected more severely than adults and may have permanent neurologic damage. Death occurs in about 3 percent of cases. Venezuelan equine encephalitis is very rare in the U.S. Children are at greatest risk of developing severe complications, while adults generally develop flu-like symptoms. Epidemics in South and Central America have killed thousands of persons and left others with permanent, severe neurologic damage.