Horses are known as a dead-end host of West Nile virus, that
is, they can become ill with West
Nile virus, but they do not maintain
sufficient virus in the blood to infect either other mammals (including humans)
or mosquitoes. Surveillance of horses has occurred in areas with a history of
West Nile virus and in additional States on the eastern coast of the United
States to monitor the possible spread of West Nile virus. This surveillance consists of
investigating suspect cases in horses. Because horses are not known to play a
role in transmission of West Nile virus, quarantines were never placed on any non-clinically
ill horses in the outbreak area. However, some foreign countries have banned the
importation of horses from New York.
The agriculture department recommends eliminating standing
water where mosquitoes breed; put
horses
inside at dawn, dusk and night; use fans to create air movement over stabled
horses; remove all birds that are in or close to stables; use insect repellant
or fog stables with pesticides in the evening.