As of June 30, Florida state officials report four times as many cases of Eastern Equine Encephalitis as were reported in each of the previous two years.

Florida Agriculture and Consumer Services Commissioner Charles H. Bronson urged horse owners to have their animals vaccinated.

Mosquitoes transmit EEE, a viral infection that affects a horse's central nervous system. 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.

Horse owners in southern states should discuss a vaccination plan with their veterinarians. "For horses, this is very serious," Terence McElroy, spokesman for the Florida Agriculture and Consumer Services Commission told The News Herald, of Tallahassee. "We're talking an 80 percent or higher fatality rate."

Since mosquitoes congregate in stagnant water, veterinary health officials recommend removing unused buckets, troughs, tires, kiddie pools, drains and other containment areas.

Also, keep horses inside or in mosquito-free areas around dusk, and use a repellent rated for mosquitoes.