EASTERN EQUINE ENCEPHALITIS - EEE

With the recent hurricane "Irene" horse owners have become worried about EEE (Eastern Equine Enciphalitis). Here is some information that should help when conditions are favorable for mosquitoes and the spread of EEE.

EEE is a viral disease that affects the central nervous system of many species of animals but is most often detected in birds and horses. The disease is transmitted to horses, and sometimes humans, by mosquitoes that have become infected after feeding on birds, which are circulating the virus. This is known as the mosquito/bird transmission cycle. It is important to remember that the virus is not transmitted directly from an infected horse to other horses or people.

Signs in infected horses can be varied but usually begin with fever, depression and listlessness, which then progress to more serious neurologic signs such as in-coordination, stumbling, circling, head pressing, coma and usually death. Once a horse becomes infected with the EEE virus and develops neurologic signs, the disease is fatal in roughly 90% of cases.

In most reported cases, the infected horses are four years or younger and are not current on vaccination against EEE. The initial series of two vaccinations should be given four weeks apart followed by semiannual boosters. In years with an above-average incidence of EEE, vaccination boosters given three times a year are recommended. Ask your veterinarian at what age to begin and the frequency of foal vaccination, as it differs from adult horses.

The use of vaccine to protect horses against EEE and other encephalitic disease, such as West Nile, is only a tool and should be used in conjunction with good mosquito reduction and avoidance measures implemented to protect yourself and your horse. The key is mosquito control to stop the mosquito/bird infection cycle. The most effective method is to destroy the mosquito larval habitat by removing all potential sources of stagnant water, in which mosquitoes might breed. Mosquitoes can breed in any puddle that lasts more than four days. Water buckets, water troughs, wading pools, birdbaths, wheelbarrows, clogged roof gutters, discarded tires, plastic containers or any water-holding container should be cleaned or emptied on a weekly basis. Drill holes in the bottom of containers that are left out-of-doors, turn over wheelbarrows, aerate ornamental pools and stock them with fish or chlorinate them.

In addition to reducing mosquito populations, preventing animals from being exposed to adult mosquitoes is important. Horses should be stabled inside during peak mosquito feeding times, which are dawn and dusk. Use of mosquito-resistant structures such as well-maintained insect screening and fans may reduce potential access of mosquitoes to equine and other livestock hosts. Insect repellants can be effective for humans and have some limited value for horses as well.

Horse owners should use repellents approved for use on horses, but the effectiveness of some formulations under certain conditions (e.g., rain, perspiration) may be limited. Always follow label instructions. Horse owners are encouraged to contact their veterinarian immediately should they notice any signs or symptoms of EEE infection in their horses, especially those exhibiting neurological signs.

This article came from the website : to veiw the whole article click on the link : http://www.freshfromflorida.com/ai/main/eee.shtml

Laura Martin

Wake County Livestock Agent