The USDA National Veterinary Services laboratory in Ames, Iowa has confirmed that two more horses submitted for testing by the Virginia Department of Agriculture and Consumer Services are positive for Eastern Equine Encephalitis (EEE). These horses, one from Suffolk and one from Prince George County, were submitted for testing on August 3rd. Another horse from the Suffolk area was submitted for necropsy on August 7th and testing is currently underway.

This makes a total of nine horses submitted to the laboratory with five confirmed by virus isolation as EEE, two more with compatible histologic brain lesions but no virus isolation confirmation, one with no histologic lesions and no virus isolation confirmation, and one just starting the diagnostic process.

The Department began an informational campaign two weeks ago advising horse owners to vaccinate their animals every six to twelve months against the disease. This is particularly important in the Southeastern region of Virginia, where they recommended the six-month vaccination interval. None of the horses that have died had been vaccinated within the last year. Veterinarians report that the publicity generated by the outbreak has spurred vaccination efforts by owners.

Generally, EEE is transmitted by mosquitoes. Typical symptoms include staggering, circling, depression, loss of appetite and sometimes fever and blindness. There is no cure for the disease, but it can be prevented through vaccination. Other prevention methods include destroying standing water breeding sites for mosquitoes, use of insect repellents such as DEET, and removing animals from mosquito infested areas during peak biting times, usually dusk to dawn