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What You Need To Know About West Nile Virus In San Diego County

West Nile Virus In San Diego County - What You Need To Know


Dr. Steve Waterman, lead, U.S. - Mexico Unit, Centers for Disease Control and Prevention

Chris Conlan, supervising vector ecologist, Dept. of Environmental Health, San Diego County.


Last week, a bird in unincorporated El Cajon tested positive for West Nile virus. It's the second bird to test positive this year, and county health officials are urging people to take precautions.

Hot and humid weather provides the perfect breeding ground for mosquitoes — and that's causing concern for San Diego County health officials as our region continues to experience warm weather and high humidity.

Just last week, a second dead bird tested positive for West Nile virus in unincorporated El Cajon.

The dead hawk was found two weeks after a Santee man was diagnosed with the disease. He's the first person in the county in two years to contract West Nile, a disease transmitted by mosquitoes.

The California Department of Health reported 16 new human cases of the disease last week in Butte, Fresno, Madera, Orange, Sacramento, Stanislaus and Tulare counties.

Chris Conlan, the supervising vector ecologist with the San Diego County Department of Environmental Health, said these reports raise alarm. But he said it's not a major threat yet.

"It's a definite sign that things could potentially progress to get a little bit worse, so people should be taking the proper precautions to prevent themselves from getting mosquito bites," he said.

Conlan said people should wear bug repellant, long sleeves and long pants to deter mosquitos. He also wants people to dump out anything around their homes that hold water, which can create a mosquito breeding ground.

He said it's difficult to say whether the recent heat and rainfall might be leading to more occurrences of the disease.

"We know heat does play a role, and the fact that we recently got rain could potentially increase the number of mosquitos," he said.

The public should report dead crows, ravens, jays, or birds of prey on the county website, or by calling (858) 694-2888, Conlan said.

San Diego County has also developed an app called Fight the Bite that allows residents to report mosquito breeding and dead birds for testing.

"We use testing to help monitor progression of the disease," Conlan said. "The more positive birds we find, the more concerned we get."

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