National Guard to help fight mosquitoes

Published 12:00 am Monday, August 12, 2002

After having caused death or illness in several states, including Louisiana and Mississippi, the West Nile virus is beginning to make its impact felt in Alabama.

The first confirmed cases of the mosquito-related virus were reported in the state last week, including a 71-year-old Dale County man and a 47-year-old Houston County man. who was hospitalized after contacting the virus and he has since been released.

Governor Don Siegelman

recently asked the Alabama National Guard to assist in the efforts to eradicate mosquitoes, especially in locations which are not being sprayed already by cities or other agencies.

As concerns about the disease continue to grow,

more precautions are being taken around the state in an attempt to combat the virus, including increased spraying, adults keeping their children indoors and stepped-up attempts to remove standing water.

The virus is beginning to affect humans in the state, but it has not been kind to animals, either.

Horses are an important part of many lives in Alabama, and it is important to note that the lives of those horses can be affected by West Nile.

Two horses have died from the virus in Dale County and Barbour County and there have been four total cases confirmed in Baldwin, Dale and Coffee counties.

According to the Centers for Disease Control, while data suggest that most horses with West Nile virus recover, the virus has caused deaths in some in the U.S.

Horses become infected with the disease the same way humans do, through the bite of infectious mosquitoes. The virus is located in the mosquito's salivary glands. When mosquitoes bite or feed on the horse, the virus is injected into its blood system. The virus then multiplies and may cause illness. The mosquitoes

become infected when they feed on infected birds or other animals.

Following transmission by an infected mosquito, the virus multiplies in the horse's blood system, crosses the blood brain barrier

and infects the brain. The virus interferes with normal central nervous system functioning and causes inflammation of the brain.

There is no documented evidence of person-to-person or animal-to-person transmission of the virus. Normal veterinary infection control precautions should be followed when caring for a horse suspected to to have West Nile or any viral infection.

There is also no documented evidence that West Nile virus is transmitted between horses, however, horses with suspected West Nile virus should be isolated from mosquito bites if at all possible.

If a horse is being vaccinated against eastern equine encephalitis (EEE) western equine encephalitis (WEE) and Venezuelan equine encephalitis, these vaccines will not protect a horse against the West Nile virus because the other viruses belong to a family of viruses for which there is no cross protection.

It is not known whether an infected horse can be infectious, although previously published data suggest that the virus is detectable in the blood for only a few days.

There is no reason to destroy a horse because it has been infected with the West Nile virus, as data suggest that most horses actually recover from the infection.

Treatment would be supportive and consistent with standard veterinary practices for animals infected with a viral agent.