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The first human case of West Nile virus infection in Los Angeles County for the year has been reported, health officials said Tuesday.

The patient, who was only described as a resident of the South Bay, was hospitalized with West Nile virus fever in late July and is recovering, the L.A. County Department of Public Health said in a news release.

“We all have to take steps to prevent West Nile virus infections. Spread by mosquitoes, this virus is the leading cause of mosquito-borne disease in the continental United States. There are no vaccines to prevent or medications to treat WNV in people,” county Health Officer Muntu Davis said in a written statement. 

Humans get the virus through the bite of an infected mosquito. While not all mosquitoes carry the virus, the type of mosquito that spreads this virus is found throughout Los Angeles County.

Symptoms of West Nile virus can include fever, headache, nausea, body aches, and a mild skin rash.

But in those over the age of 50 and those with chronic medical conditions, severe infection can occur and affect the brain and spinal cord resulting in meningitis, encephalitis, paralysis and even death, the Health Department said.

In Los Angeles County, an average of 118 cases per year have been documented during the previous five years. Officials said the total number of people infected with the virus each year, locally, is much higher as most infected persons do not experience any illness or only mild illness.

“About three-quarters of reported cases have had severe disease and approximately 9% of patients with severe WNV die from complications,” Davis said.

L.A. County Public Health recommends the following actions to reduce the risk of West Nile virus infection:

  • Avoid mosquito-infested areas at dawn and dusk.
  • Use insect repellent. Use Environmental Protection Agency (EPA)-registered repellents containing DEET, picaridin, IR3535, oil of lemon eucalyptus (OLE), para-menthane-diol (PMD), or 2-undecanone. When used as directed, EPA-registered insect repellents are proven safe and effective, even for pregnant and breastfeeding women. Find the right insect repellent for you by using EPA’s search tool.
  • Cover up. Consider wearing long-sleeved shirts and long pants when you are outdoors, particularly at these times and in areas where more mosquitoes are present.
  • Take steps to control mosquitoes indoors and outdoors.
  • Use screens on windows and doors. Check for and repair holes in screens to keep mosquitoes outdoors.
  • Stop mosquitoes from laying eggs in or near water. Once a week, empty and scrub, turn over, cover, or throw out items that hold water, such as tires, buckets, planters, toys, pet bowls, flowerpot saucers, rain barrels, or other containers. These are where mosquitoes lay eggs.
  • Empty and wash birdbaths and wading pools weekly.
  • Clean and chlorinate swimming pools; drain any water collecting on pool covers.
  • Stock garden ponds with mosquitofish (Gambusia affinis), goldfish, Koi or other mosquito-eating fish. These feed on mosquito eggs and larvae.

Anyone who sees a stagnant swimming pools or “green pools” can report them to the Public Health Environmental Health Bureau at 626-430-5200, or to a local vector control agency. Dead birds may be reported by calling 877-968-2473 or online at

For more information on West Nile virus, visit, and to find a local vector control district visit