VOLUSIA COUNTY -- Three horses in Volusia County and one in Lake County have come down with Eastern Equine Encephalitis.
Now health workers fear the mosquito that transmitted it to horses could bite humans.
All of the horses had to be euthanized. A fourth horse in Volusia County i suspected to also have EEE.
Mosquito Control has stepped up its testing efforts since mosquitoes tested positive for EEE in three different parts of Volusia County.
"It is of concern because the mosquito that bit the horses can bite humans,” said Paul Minshew from the Volusia County Health Department.
EEE is fatal in 30 to 40 percent of human cases.
Those most susceptible to the mosquito borne illness are the elderly over 55 years old and children under 15.
State and county health officials are expected to issue an Easter Equine Encephalitis advisory by Thursday.
According to the Rutgers Cooperative Extension, the virus responsible for EEE attacks the nervous system and horses are particularly susceptible to the infection. It is almost always fatal in horses.
Symptoms include unsteadiness, erratic behavior and a marked loss of coordination. There is no effective treatment and seizures resulting in death usually occur within 48 to 72 hours of an animal's first indications of illness.
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