EEE: Florida Horse Owners Cautioned about Spike in Cases

Florida horse owners are being urged by Florida Agriculture and Consumer Services Commissioner Charles Bronson to get their animals vaccinated following an upsurge in the number of Eastern Equine Encephalitis (EEE) cases.

According to the USDA, in 2009 Florida led the country in number of confirmed EEE cases with a total of 75, with Volusia County leading with way with 10 cases. So far this year there have been 16 confirmed cases of EEE in horses in Florida. Seven of the cases were reported on June 23 from counties scattered throughout the state. It has been reported that horses in Collier and Jackson counties (two total) have been euthanized due to the disease.

"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 West Nile virus (WNV) activity in sentinel chickens in the southern part of the state, including Martin County, which has not had EEE detected in 30 years. I want to remind horse owners of the importance of getting their animals vaccinated."

Why the stress on the chickens? "Chickens are our surveyors. They're our indicators that, 'Hey, it's active. It's here, and mosquitoes are carrying this,'" Darrell Harvey, DVM, with Van Roekel & Associates, located in Alva, Fla., told the Naples Daily News.

EEE is a viral disease that affects the central nervous system and is transmitted to horses by infected mosquitoes. The fatality rate for EEE in horses is 75-95%. The course of EEE can be swift, with death occurring two to three days after onset of clinical signs, despite intensive care. Horses that survive might have long-lasting impairments and neurologic problems. Clinical signs for EEE include moderate to high fever, depression, lack of appetite, cranial nerve deficits (facial paralysis, tongue weakness, difficulty swallowing), behavioral changes (aggression, self-mutilation, or drowsiness), gait abnormalities, or severe central nervous system signs, such as head-pressing, circling, blindness, and seizures.

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 foolproof method to prevent the diseases, vaccinations are critical.

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About the Author

Megan Arszman

Megan Arszman received a Bachelor of Science In print journalism and equine science from Murray State University in Murray, Ky., and loves combining her love of horses, photography, and writing. In her “free time,” when she’s not busy working as a horse show secretary or riding her American Quarter Horses on her parents’ Indiana farm, she’s training and competing her Pembroke Welsh Corgi and Swedish Vallhund in dog agility and running.

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