'Factual' information gathered on West Nile virus

By MANDY JOHN | Central Texas Edition

Dr. Jim Olson holds up a napkin with mosquito eggs taken from a paper cup full of water. -Staff photo by John

August 29, 2002 -- A state-wide media advisory titled "A Bird's Eye View of West Nile virus in Texas" took place on Aug. 22, 2002 in San Antonio, New Braunfels, Uvalde, and College Station. The purpose was to present solid, factual information about the West Nile virus disease and different ways humans can protect both themselves and their animals.

Last week, McLennan County was added to the Texas West Nile case list after several dead birds, found inside the city limits of Waco, were sent to the Texas Department of Health to be tested for the presence of West Nile virus. Only one result has come back and it was negative. It was also reported that a Waco woman was taken to the hospital after suffering symptoms similar to West Nile.

"West Nile virus was first discovered in New York City in 1999," said Bruce Lawhorn, associate professor and Extension veterinarian for Texas A&M University who was speaking from the College Station venue. "Previously it had been confined to Africa, Europe, Asia and the Middle East." He stated that it is believed that the virus traveled to the United States by both birds and mosquitoes.

Lawhorn explained that West Nile is a viral infection that has been discovered in birds, horses, and now, humans. The virus can cause encephalitis, a swelling of the brain. Eight-five percent of those infected with the virus will suffer symptoms such as stumbling, staggering, fever, headache and body aches. More severe cases can result in coma, paralysis or death. West Nile can mimic other diseases, including rabies, or other encephalitic diseases, such as Western Equine Encephalitis and Eastern Equine Encephalitis.

"uUnlike rabies and other encephalitic diseases, West Nile can't be transmitted directly," he said. At this time, the only known way to transmit the virus is through mosquitoes. Lawhorn suggested that ranchers should vaccinate their horses now and use techniques to minimize mosquito contact.

If a horse is found out to have the virus it needs to be reported to the Texas Department of Health right away. The Texas Health Department has set up a toll free number, 1-888-883-9997, and a website, texaswestnile.org, specifically for West Nile cases and questions.

"While a vaccine is available for horses, the animal must receive two doses of the vaccine three to six weeks apart. Full protection does not begin until at least four weeks after the second dose of vaccine is administered. " After that, a yearly booster is needed, Lawhorn said.

"The mosquitoes are what put the disease cycle in motion," stated Jim Olson, professor with the Texas Agricultural Experiment Station at Texas A&M University. "After the mosquitoes feed on infected birds they become infected and transmit the virus to both horses or humans."

Olson gave three proofs to protect against West Nile virus. The first is to protect oneself by wearing long sleeve shirts, pants and mosquito repellent when going outside. The second is to protect animals by keeping them in the house whenever possible. If this is not a possibility, make sure that articles are not left out in the open to collect water or hold water around for mosquitoes. Lastly, he suggested spraying for mosquitoes inside and around the house, as well as inside stables.