A Columbia resident has likely contracted West Nile virus, according to the Columbia/Boone County Health Department.
It is the first probable case of West Nile virus in Boone County this year. Although the identity of the patient is confidential, representatives from the health department said she is a female, older than 50, who lives in southwest Columbia, near the Country Club of Missouri. The woman was hospitalized a few days ago with many symptoms of the virus.
Although doctors say tests will confirm the presence of the virus, final test results of her spinal fluid are still pending. She is at home recovering.
“The person hospitalized had many symptoms,” said Heather Baer, public information specialist of the department. “The Missouri Department of Health and Senior Services is confident enough (that the disease was West Nile virus) that they are going to post the case online.”
West Nile virus is spread to humans, birds and various animals through mosquitoes. The insects transmit the virus from wild and domesticated birds to other birds and mammals.
As a preventative measure, the health department will be spraying a half-mile section around the area where the victim was likely infected. Workers will spray trees, lawns, and any areas of standing water with a nontoxic chemical developed to affect only mosquitoes. It won’t hurt pets, children or vegetation. The treatment will take place at either dawn or dusk.
“We like to work when mosquitoes are most active,” Baer said.
Boone County only had one human case of West Nile virus in 2003, compared with 64 cases statewide. This year, there have been six confirmed cases in Missouri as of Sept. 7. Eight people in the state died from the virus in 2003, but none of this year’s cases has been fatal. West Nile cases tend to peak in late summer and early fall.
The Centers for Disease Control and Prevention says the likelihood of becoming infected with West Nile virus is very small. Less than 1 percent of mosquitoes carry the virus, and less than 1 percent of humans bitten by an infected mosquito will contract West Nile. “Most people who get it don’t even realize they have it,” Baer said. “They may just think they felt a bit sick for a day or two.”
Those who do show symptoms will do so three to 14 days after exposure. Symptoms include slight fever, headache, body aches, skin rash and swollen lymph nodes. Symptoms are more likely to occur in children and older adults, and those who are already sick or have a chronic disease.
Researchers track the virus in animals to help study it.
“Our role is to protect humans by determining where the disease is in animals,” said Gayle Johnson, MU associate professor of veterinary pathobiology. “We use testing to verify the virus’ presence.”
As of July 26, Boone County had eight birds that tested positive for the virus. Johnson said that number was fairly substantial.
The health department says the best way to prevent West Nile virus is to reduce the risk of mosquito bites.