Florida is experiencing an increase in the mosquito-borne virus Eastern equine encephalitis, health officials warned in a July 25 statement, according to CNN.
Several sentinel chickens tested positive for EEE, which causes brain infection and swelling and spreads to humans via infected mosquitoes. Sentinel chickens, or fowl tested regularly for West Nile virus and EEE, exhibit the diseases in their blood but experience no side effects.
"The risk of transmission to humans has increased" due to the chickens' positive test results, said the Florida Department of Health.
The U.S. typically reports an average of just seven human EEE cases per year, but 30 percent of those who catch the disease die, according to the CDC.