Valley's dry conditions could lead to more mosquitoes carrying West Nile virus

FRESNO, Calif. (KFSN) -- Summer is here and so is the busy mosquito season.

But as California deals with another drought year, less water could mean more mosquitoes carrying a potentially life-threatening virus.

"Traditionally in a drought year, we expect to see lower numbers of mosquitoes and higher disease presence," says Mir Bear-Johnson.

On Wednesday morning, The Delta Mosquito and Vector Control District plan to treat some neighborhoods in Visalia with low doses of adulticides for mosquitoes.

This comes after 22 mosquito samples out of more than 440 came back positive for West Nile, while four out of nine birds tested also came back positive for the virus.

The culex mosquito is known for transmitting the disease, and mosquito district officials say that number of positive samples is average this time of year. The dry year can cause other issues.

"There are fewer water sources," Bear-Johnson said. "So the birds and the mosquitoes all have to congregate a little closer together, to take advantage of the water sources that do exist, which increases the likelihood of virus transmission between the two."

Katherine Ramirez with the Consolidated Mosquito Abatement District says they've also has positive west Nile samples, and also use ultra low volume treatments when found.

She recommends insect repellent at dawn and dusk when the mosquitoes are more likely to bite and report or dump standing water.

"If you find larvae in water, if you dump it out, they're going to die," she said. "Dump any type of water."

She also suggests inserting a piece of a window screen, or a foam insert in yard drains to prevent a breeding ground.
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