Carson City officials unsure of 2005 mosquito threat

Carson City health officials are gearing up for the 2005 mosquito season, the second season in which West Nile virus will be in Nevada.

There's no way to tell if the mosquito-borne disease will have a sizable effect on Carson City, said public health specialist Darren Winkelman, but city officials are keeping strict surveillance just the same.

"We think it's a big issue, not just because of health aspects but because they (mosquitoes) are a nuisance, too," Winkelman said.

Nevada's first case of the West Nile Virus was found in Carson City last July, detected in a dead bird.

Since then, however, the disease has rarely manifested itself in the city.

Only one of the state's 44 human cases was recorded here, while nearby Churchill County, with a population about half the size, racked up 15. And of 116 animals reported to have been infected, nearly all horses, six were in Carson City.

But Northern Nevada's wet winter will likely lead to a skyrocketing mosquito population this summer, and unpredictable conditions from county to county.

Usually, Carson City health officials know they have to spray larvicide on about 400 acres of the Anderson Ranch property in east Carson City before mosquito eggs hatch. They also have several known pockets of water programmed into GIS equipment where they also spray.

But this year, "there are pockets of water where we haven't seen them before," Winkelman said.

Good for farmers and good for the water table, this year's drought-relieving weather also promises to be a boon for mosquitoes that now have an abundance of breeding ground throughout the state.

Along with a higher mosquito population is the concern that this year will be the area's second dealing with the disease.

A trend that has appeared as West Nile virus spread from New York to the rest of the nation over the past six years, is that it's at its worst the second year in an area.

The most exaggerated example of the second-year jump is Colorado, where human infections skyrocketed from 14 in 2002 to 2,947 in 2003 and back down to less than 300 in 2004.

Nevada State Veterinarian David Thain said earlier this month that state officials expect a West Nile rate three times higher than last year.

Surveillance will be Carson City's main focus, Winkelman said. Helicopters and resident tips will help mosquito abatement officials find new pools of water and pockets of mosquitoes to spray.

"We want to be on top of it and we are on top of it."

The virus causes mild flu-like symptoms in the vast majority of people it infects, but a small percentage of people develop more severe forms of illness that swell the brain and spinal column, sometimes leading to death.

In 2004, 2,470 human cases and 88 deaths were reported nation wide.

Horses, which can be inoculated against the virus are far more susceptible to it. Of 130 horses confirmed to have West Nile virus last summer, 50 died.

-Contact reporter Cory McConnell at cmcconnell@nevadaappeal.com or 881-1217.