Long Beach confirms first case of mosquito-borne St. Louis encephalitis in decades

Long Beach's health department has confirmed the first case of a mosquito-born illness called St. Louis encephalitis in the city since 1984.

The risk of exposure in the city is low and the Department of Health and Human Services is taking steps to try to prevent the spread of the virus, according to a department news release. The person who was infected was hospitalized and is recovering at home. No other cases have been identified in Long Beach.

As of Nov. 3, a dozen cases of St. Louis encephalitis have been detected in the state this year.

"We are working diligently with healthcare providers to educate the community to prevent more cases of SLEV,” Mayor Rex Richardson said in the news release. “Mosquito control is a shared responsibility and residents must take an active role in reducing the threat of mosquito-borne illnesses in their neighborhoods.”

Read more: Rare case of mosquito-borne dengue diagnosed in Pasadena

The disease is spread by the bites of infected Culex mosquitoes and is in the same virus family as West Nile virus, with similar transmission and symptoms, according to the health department. The disease isn't spread from person to person and most people infected by a mosquito won't have symptoms.

People over the age of 50 and those with underlying health conditions have a greater risk for serious symptoms, which can affect the nervous and brain system, resulting in confusion, stiff neck, dizziness and death, health officials said.

The news of the disease comes only weeks after health officials in Pasadena detected a case of locally acquired dengue, a virus transmitted by mosquitoes.

Mosquitoes that spread such diseases are more active at dawn and dusk. Experts say residents should use mosquito repellent containing DEET or other chemicals, wear loose-fitting clothing, eliminate standing water around anything that holds water for more than a week and keep weeds, hedges and vines trimmed.

“The first confirmation of SLEV in Long Beach should serve as a reminder that we need to protect ourselves against mosquitoes,” said Dr. Anissa Davis, the city's health officer. “The Health Department encourages everyone to continue reporting issues regarding mosquito control in their area."

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This story originally appeared in Los Angeles Times.