West Nile virus is no cause to alarm people
Utah residents and Utah State University students can rest assured this summer.
The West Nile virus is nothing to become alarmed about, according to government officials and researchers across the state.
Although the virus affects mainly humans, horses and birds, most people who become infected with it will have either no symptoms or only mild ones, according to the Centers for Disease Control and Prevention Web site, www.cdc.gov.
Craig Day, a USU doctoral student who has researched the virus, said more people die from influenza every year than from the virus.
“People shouldn’t be that scared. They don’t need to worry about dying,” Day said.
It is estimated that 20 percent of the people who become infected will develop West Nile fever, accompanied by mild symptoms, including fever, headache, body aches, and occasionally a skin rash on the trunk of the body and swollen lymph glands, according to the CDC Web site.
Less than one in 1,000 people die from the virus, and they are all over 50 years old, Day said.
The virus has not spread to Utah yet but is expected to do so in the next couple of months.
“We expect it to spread sometime this summer and to be here at a fairly high level for a couple of years,” said Gary Hatch, manager of the Davis County Mosquito Abatement District.
Birds carry the virus, and mosquitoes spread it to other birds, animals or humans, according to a USU Extension pamphlet on the virus.
John Morrey, USU research professor, said WNV is part of a modern phenomenon called emerging viruses. Because of modern technology, people have the ability to travel to highly concentrated populations around the world. So, if a virus emerges, it has a greater potential to spread.
Other examples of emerging viruses include human immunodeficiency virus, ebola haemorrhagic fever and severe accute respiratory syndrome, Morrey said.
WNV is established enough that it is here to stay but will subside.
“It will settle down. It’s like a fire that burns itself down a while and isn’t so intense,” Clell Bagley, USU Extension veterinarian, said.
Utah is one of the last five states in the United States that have not become infected with the virus since its outbreak during the summer of 1999 in New York.
“It’s been in most of the western states, and it is expected to come into the state this year,” Eleanor Jenson, USU Extension veterinarian, said.
Although residents should not be alarmed by the virus, they should still take precautions.
The Utah Department of Health is teaming up with other government entities to combat the spread of the virus with a surveillance program called “Fight the Bite.”
People can prevent themselves from being infected by staying indoors at dusk and dawn, when mosquitoes are most active, wearing protective clothing, removing any still water where mosquitoes can lay eggs, and using repellent containing DEET.
“DEET is the active ingredient in repellent, and it has been found to be the most effective repellent at this point in time,” Hatch said.
The “Fight the Bite” program will also include seasonal trapping and testing of mosquitoes, testing of chickens and select dead birds, monitoring for WNV infections in people or horses, and providing information about WNV, according to http://health.utah.gov.
Precautions within Cache County
Bryan Lay, from Logan City Animal Control, said his organization is testing any dead birds, such as crows and raptors, for the virus. People who find dead birds are encouraged to report them to their local animal control officers.
Max Gyllenskog, an epidemiologist at the Bear River Health Center, said the center is also going to encourage the public to look for dead birds. He and his colleagues expect to be very busy this summer because of the virus.
Jim Davis, director of the Student Health and Wellness Center, advises students to come in to be evaluated and start treatment right away if they think they are infected.
Entomologist Elmer Kingsford is making his fourth attempt since 1958 to get a Cache County mosquito abatement district. He said he hopes with the threat of WNV, more people will support the district.
If the district is built, it would provide professionals and equipment to inspect where most of the mosquitoes in Cache County are breeding and decrease the mosquito population, Kingsford said.
“We have a great recreational area year-round, but in the summer months, it’s a problem because of the mosquitoes,” he said. “With the abatement district, people will be able to use their backyard barbecues a little easier.”
Each city council in the valley has to pass a resolution for the district. After a hearing process, residents will vote on it in November. If passed, it will be funded through property taxes.
Infected horses
Although the virus is not as life-threatening in humans, it is consistently fatal in horses. In 2002, there were almost 15,000 confirmed cases of WNV in equines, according to the USU pamphlet.
However, a vaccine is available for horses that is 94 percent effective. The vaccine is $20 per dose and requires two doses to be effective.
Bagley said $20 is expensive for what veterinarians usually expect to pay.
At Yardley Cattle Company in Beaver, Utah, Jeannie Yardley, a junior majoring in agriculture business, said her family has vaccinated 21 mares this year.
“It’s just wise to take precautions. All you can do is give the shot and hope for the best,” she said.
Although it’s expensive, it’s worth the money, because it would cost more if their horses became infected with the virus, she said.
WNV research at USU
Researchers are still trying to find a vaccination for humans. The National Institutes of Health funded USU’s Institute for Antiviral Research to find a drug to treat WNV once someone has been infected.
“I can see in the near future having a drug that will reduce the severity of the virus, but I don’t see a drug that will eliminate the disease,” said Morrey, who has worked on the research.
The virus is very difficult to treat, because it gets in the brain. Drugs cannot cross the brain’s membrane to treat the virus. By the time most people realize they are infected, the virus is already in the brain, Day said.
Morrey and Day have been working on a treatment for the virus since its outbreak in 1999.
Out of hundreds of compounds they have tested, only about five seem promising, Morrey said.
The NIH will fund clinical tests in the near future on two drugs, interferon and gammaglobulin. Medical doctors will use the information from those trials to try to develop a treatment for the virus.
Aside from Morrey and Day, two doctoral students and four technicians have worked on the research.
History of the virus
The WNV is commonly found in Africa, West Asia and the Middle East. Until 1999, the virus had not been documented in the Western Hemisphere, according to the CDC Web site.
The virus became recognized as a cause of severe inflammation of the spinal cord and brain in elderly patients during an outbreak in Israel in 1957, according to the Web site.
-mmackay@cc.usu.edu