LOS ANGELES (CBSLA.com) – A Los Angeles County resident was among three people confirmed as the state’s first deaths this year due to West Nile virus, the state Department of Public Health announced Friday.

No details were released about any of the three patients, although the other two deaths were residents of San Bernardino and Kern counties.

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As of Sept. 1, there were 87 human cases of West Nile virus in 13 counties across the state. Of those, 39 were in L.A. County, 12 in San Bernardino County, five in Orange County and three in Riverside County.

Last month, the Greater L.A. County Vector Control District noted in a marked increase in West Nile virus activity in the San Fernando Valley.

Symptoms of the virus — which is transmitted by mosquito bites — can include fever, body aches, rash, nausea, vomiting and headaches, but many people who are infected may not show any symptoms. About one in 150 people could develop more serious problems, such as brain inflammation or paralysis, health officials said.

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“West Nile virus can cause a deadly infection in humans, and the elderly are particularly susceptible,” State Health Officer Dr. Karen Smith said. “August and September are peak periods of West Nile virus transmission in the state so we urge everyone to take every possible precaution to protect themselves against mosquito bites.”

People spending time outdoors are advised to wear mosquito repellant and treating their clothing with permethrin products to prevent bites. The CDC recommends products with the active ingredients of DEET, Picaridin or IR3535. For children, parents should only use EPA-registered repellants.

You should also regularly replace any standing water around your home – such as flower pots and pet dishes – which can serve as a mosquito breeding ground.

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