Mosquitoes trapped near Clarkdale tested positive for West Nile virus, the first confirmed report of the disease in Arizona this year, Yavapai County Community Health Services officials confirmed Thursday, May 3.

Mosquitoes trapped near Clarkdale tested positive for West Nile virus, the first confirmed report of the disease in Arizona this year, Yavapai County Community Health Services officials confirmed Thursday, May 3.

"This is the first positive to be found in Yavapai County and it is the first in the state," YCCHS Director Robert Resendes said.

Yavapai County reported no cases of West Nile virus in 2006 compared to 77 human cases in Maricopa County during the same period, Resendes said.

"No human cases reported in Arizona so far this season, knock on wood," he said.

The county's aggressive mosquito eradication program could explain the low incidence of the virus last year, he said.

Resendes, appointed county health director about eight months ago, asked the Yavapai County Board of Supervisors on Monday, April 30, for a budget increase of $105,000 to fund the mosquito eradication program.

County budget deliberations are ongoing.

Yavapai County epidemiologist Stephen Everett, who keeps track of West Nile virus and other diseases in the county, said Yavapai County reported no cases in mosquitoes, horses, birds or humans last year.

The symptoms of West Nile virus and the flu are so similar, the only way to know if a person is infected is through a standard blood test, Everett said.

"People who are older or have health problems need to go in to be tested, especially if they know they have been bitten," Everett said.

Licensed physicians and other qualified health care workers can perform the test, he said.

Just one human case of the virus was reported in each of 2004 and 2005, he said.

Everett said 80 percent of people bitten by mosquitoes that carry West Nile virus will not be infected. Most of the remaining 20 percent suffer mild symptoms and recover within days, or possibly a few weeks.

Elderly people and others with weaker immune systems can be hospitalized with the infection and some die, he said.

"One out of 150 people will have serious symptoms, including meningitis to encephalitis," which are life-threatening, Everett said.

Now that the virus has been confirmed in the county, it's only a matter of time before more cases are reported, Resendes said.

"It"s likely to spread," he said.