Simple Steps Can Help Prevent West Nile Virus and Other Mosquito-Borne Disease

June 21, 2023 - As spring days become warmer - and mosquitos more common - the Los Angeles County Department of Public Health advises all residents to take precautions now to help prevent mosquito-borne diseases.

Illnesses such as West Nile virus and Saint Louis Encephalitis virus can be spread through the bite of an infected mosquito here in Los Angeles County. Public Health recommends the following actions to reduce the risk of West Nile virus and other mosquito-borne disease infections:

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 standing 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 places 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 fish that eat mosquitos such as mosquitofish, goldfish, or koi. These feed on mosquito eggs and larvae.

Avoid outdoor activities at dusk and dawn during warm mosquito season when mosquitoes are most active.

Use insect repellant. Choose 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. Wear long-sleeved shirts and long pants when you are outdoors, particularly at dusk and dawn, and in areas, where more mosquitoes are present, such as ponds with stagnant water.

Report stagnant swimming pools or "green pools" to the Public Health Environmental Health Bureau at (888) 700-9995, or to a local vector control agency.

Dead birds should be reported to the California West Nile Virus Dead Bird Hotline at (877) 968-2473 or online: https://westnile.ca.gov/report.php

"The best ways to prevent West Nile virus infections and other mosquito-borne diseases is to take steps now to eliminate mosquito breeding spots and to protect our families from bites," said Dr. Barbara Ferrer, Ph.D., M.P.H., M.Ed., Director of the Los Angeles County Department of Public Health. "Because there are no vaccines to prevent West Nile, or a treatment to cure this disease, we can all follow simple steps to reduce the risk of West Nile virus including removing standing water around our homes and avoiding mosquito-infested areas at dawn and dusk."

About West Nile Virus

West Nile virus is the leading cause of mosquito-borne disease in the continental United States and each year cases are detected among residents in Los Angeles County.

While everyone is at risk for West Nile virus, people over age 50 and those with health problems are at greater risk of serious illness. West Nile virus can affect the nervous system and result in meningitis, encephalitis, limb paralysis and even death.

Symptoms may include fever, headache, nausea, body aches, and a mild skin rash. Severe symptoms include high fever, muscle weakness, neck stiffness, confusion, as well as coma.

While not all mosquitoes carry West Nile virus, the type of mosquito that spreads this virus is found throughout Los Angeles County, and across the state.

For more information on West Nile virus, visit publichealth.lacounty.gov/media/westnile. To find a local vector control district that helps protect residents from mosquitos, visit http://www.socalmosquito.org.