First West Nile Virus Activity of the Year Detected in Los Angeles County
Vector Control confirmed mosquito samples collected in Long Beach and Pico Rivera tested positive for West Nile virus.
Santa Fe Springs, CA (May 20, 2026) – The Greater Los Angeles County Vector Control District (GLACVCD/District) has confirmed two West Nile virus (WNV) positive mosquito samples in Los Angeles County. The positive samples were collected from mosquito traps in the cities of Long Beach and Pico Rivera, confirming virus activity in local mosquito populations.
“West Nile virus is regularly detected in the environment throughout Los Angeles County, and these early detections are a reminder that mosquito season is already underway,” said Angela Caranci, GLACVCD Scientific-Technical Manager. “Dumping standing water, reporting neglected swimming pools, and using mosquito repellent are simple but effective ways to reduce risk.”
The native Culex mosquito can transmit West Nile virus and is most active from dusk to dawn. With no current human vaccine available for the virus, residents are encouraged to take personal protective measures by using mosquito repellent when spending time outdoors, especially during peak mosquito activity. The Centers for Disease Control and Prevention recommend using insect repellent containing one of the following active ingredients: DEET, Picaridin, IR3535, or Oil of Lemon Eucalyptus, which have been proven safe and effective when used as directed.
“The District’s mosquito control efforts are most effective when paired with community action,” added Caranci. “Residents play a vital role in reducing mosquito breeding by routinely inspecting their properties and eliminating standing water.”
Mosquito control is a shared responsibility, and residents must take an active role in reducing the threat of WNV in their neighborhoods by taking the following additional steps:
- Eliminate standing water in clogged gutters, rain barrels, discarded tires, buckets, watering troughs or anything that holds water for over a week.
- Maintain swimming pools, spas, and ponds, and report neglected or green pools to vector control.
- Change the water in pet dishes, bird baths, and other small containers weekly.
- Request mosquitofish from their local vector control district for placement in ornamental ponds.
- Report dead birds to the California Department of Public Health online at www.westnile.ca.gov or call 1-877-WNV-BIRD.
For an extensive list of common indoor and outdoor sources and recommended solutions, visit bit.ly/diy-mosquito-solutions. For more information, residents can contact the Greater Los Angeles County Vector Control District at 562-944-9656, online at www.GLAmosquito.org, or on social media: Facebook, X, Instagram, Nextdoor, and YouTube.
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About West Nile virus (WNV):
WNV is transmitted to people and animals through the bite of an infected mosquito. There is no cure for WNV. One in five persons infected with the virus will exhibit symptoms. Symptoms can include fever, headache, body aches, nausea, or a skin rash. These symptoms can last for several days to months. One in 150 people infected with the virus will require hospitalization. Severe symptoms include high fever, muscle weakness, neck stiffness, coma, paralysis, and possibly death.
About GLACVCD:
The Greater Los Angeles County Vector Control District is an independent Special District and public health agency formed under the authority of the California State Health & Safety Code. Our mission is to promote healthy communities within the District's service area by countering the threat of mosquito and other vector-borne diseases through exceptional service, rigorous surveillance strategies, conscientious control measures, and comprehensive education efforts.