Public Health Reports First Human Case of West Nile Virus in Los Angeles County for 2026

LOS ANGELES  —The Los Angeles County Department of Public Health has identified the first case of West Nile virus or WNV infection for the 2026 season in a Los Angeles County resident. The person is currently hospitalized after developing WNV encephalitis after symptom onset in late June. The individual lives in the Antelope Valley.

“The first human cases of West Nile virus are an important reminder that we all need to take steps to prevent mosquito bites and mosquito breeding,” said Muntu Davis, MD, MPH, Los Angeles County Health Officer. “Mosquitos thrive in hot weather, increasing the risk of bites and mosquito-borne diseases. People should follow these simple steps to reduce their risk of exposure: 1) Use insect repellent on you and your family; 2) Remove items that hold standing water around your home where mosquitoes can lay eggs and breed; and 3) Use, install, or repair window and door screens to prevent mosquitoes from entering your home.”  

Public Health collaborates with local vector control agencies to target areas for mosquito control activities and engage residents to provide information about how to protect themselves.

For more information on West Nile virus, visit www.ph.lacounty.gov/WestNileVirus. To find a local vector control district, visit http://www.socalmosquito.org.

Neglected swimming pools or “green pools” that may contribute to mosquito breeding should be reported to the Public Health Environmental Health Division at 626-430-5360 or online at ph.lacounty.gov/eh/safety/public-pools.htm, or to a local vector control district for pools at single family homes.

Dead birds may be reported by calling 877-968-2473 or online: https://westnile.ca.gov/report.php