Tennessee's Department of Health is urging doctors to check patients who have sudden onsets of fever and other symptoms for West Nile virus.
West Nile virus is a flavivirus commonly found in Africa, West Asia and the Middle East. It is closely related to St. Louis encephalitis virus which is also found in the United States. The virus can infect humans, birds, mosquitoes, horses and some other mammals.
There are currently seven cases of West Nile virus in Tennessee. There are three cases in Shelby County and one case each in Green, Hickman, Chester and Haywood counties.
“It is very important for physicians to consider West Nile in their differential diagnosis when they see someone who has a sudden onset of fever,” State Epidemiologist Dr. Abelardo Moncayo said.
The department of health analyzes hundreds of pool samples every week to determine which ones have mosquitoes that test positive for West Nile virus.
Davidson County has not had any pools test positive. But, 60% of Shelby County's pools have tested positive this week.
“The more positive pools we have the greater risk out there,” Dr. Moncayo said.
According to the Centers for Disease Control so this year, 47 states have reported West Nile virus infections in people, birds or mosquitoes.
There have been 1,118 cases of West Nile virus disease in people, including 41 deaths.
More than half of those deaths were caused by encephalitis or meningitis.
The 1,118 cases is the highest number of West Nile virus disease cases reported to CDC through the third week in August since West Nile virus was first detected in the United States in 1999.
Around 75% of the cases have been reported from Texas, Mississippi, Louisiana, South Dakota and Oklahoma. Half of all the cases are from Texas.
News of the viruses spread has folks worried. The Lindsley family is visiting Nashville from Washington State. They have also made sure to keep their infant daughter Harley away from insects.
“We were getting eaten alive yesterday just from the mosquitoes,” Stephanie Lindsley said. “We have been a little bit more aware and watching out on the grass.”
The Department of Health said it is also important for people to get rid of standing water around their property.
Metro Nashville's Health Department has tablets people can put in standing water to kill mosquito larvae that have not turned into full grown mosquitoes.
- August 17, 2012: Researchers keep close eye on West Nile virus