Drought may be to blame for early West Nile Virus detection

FRESNO, Calif. (KFSN) -- A local mosquito expert says the Central Valley could be facing another record year of human West Nile cases. Fresno and Tulare counties combined last year for 64 of the state's 800 human West Nile cases, and many blame the drought.

So far this year in California, nearly 20 batches of mosquitoes have tested positive for West Nile Virus. More than half of those came from Visalia -- 12 batches, or pools. And while one local official we spoke with says that's not necessarily high, it is early.

Dr. Anthony Cornel runs the insectories at the U.C. extension center near Parlier where he does important research on vectors that can carry West Nile or other deadly viruses. The State of California had 801 human West Nile cases. There haven't been any human cases so far this year, but the reasons for the West Nile infected mosquitoes in Visalia could be two-fold, says Cornel. The first being that dry conditions are drawing birds and mosquitoes to urban areas where there's more water.

"That coupled with high temps. The virus amplifies quicker in mosquito when the mosquito is in a hot environment versus a cold environment," said Dr. Anthony Cornel, mosquito researcher.

The easiest way to prevent the spread of West Nile: get rid of standing water, and let the local abatement district know if there's a mosquito problem.

Dr. Cornel said, "People need to realize that if one person is not playing their part, by trying to reduce breeding sites for mosquitos, it puts their neighbors at risk."

Cornel and vector control are also trying to eliminate another dangerous species of mosquito that has now made its way to Clovis. As for West Nile, a dangerous disease, Cornel says it's not going away soon. "We're going to have to live with it for many more years to come."

Dr. Cornel has done mosquito research all around the world. When asked what can be done better here in California to combat West Nile. Again, he came back to everyone doing their part, to eliminate standing water, and avoid over irrigating.

The majority of those infected with West Nile do not show symptoms, but the CDC says symptoms include fever, rashes, and in severe cases, meningitis.
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