News release
The Los Angeles County Department of Public Health has identified the first case of West Nile virus infection for the 2026 season in a Los Angeles County resident, said a news release from Public Health.
The person was 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,” Dr. Muntu Davis, Los Angeles County health officer, said in the release. “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.
“Detecting West Nile virus in our district is a reminder that this virus has been present in California — and right here in our community — for over 20 years. It’s part of our local environment and continues to reappear year after year,” Brenna Bates-Grubb, community outreach specialist for the Antelope Valley Mosquito and Vector Control District, said in the release. “We urge everyone to take simple steps to protect themselves and their families: use EPA-approved mosquito repellent, keep swimming pools clean and maintained, drain any standing water around your home, and check for sources like buckets, plant saucers, or clogged gutters that can fill with rainwater. It only takes a small amount of water for mosquitoes to breed.”
West Nile Virus spreads through the bite of an infected mosquito. Symptoms may include fever, headache, nausea, body aches, and a mild skin rash. WNV can affect the nervous system and result in meningitis, encephalitis, paralysis and even death.
While everyone is at risk for West Nile Virus, adults over the age of 50 years and people with chronic health problems are at higher risk of severe illness. Although not all mosquitoes carry this virus, the type of mosquito that spreads this virus is found throughout Los Angeles County.
Public Health reports human cases of WNV every year in LA County, at an average of 41 cases per year during the past five years. However, the total number of people infected with WNV each year in LA County is much higher as most infected people do not experience any illness or only mild illness. These cases are neither reported nor recognized as WNV. Recovery from severe illness can take weeks or months and approximately one in every 10 patients with severe neurological illness die from complications. This does not include cases in Long Beach and Pasadena as cases identified in those cities are reported by their local health departments.
There is no specific treatment for West Nile virus disease and no vaccine to prevent infection. Preventing mosquito breeding and mosquito bites are the best ways to prevent WNV infection. West Nile virus spreads during warm weather months when mosquitoes are most active. The virus survives in nature in several types of birds and is transmitted by the bites of mosquitoes that feed on infected birds. The emergence of WNV cases each year can be preceded by an increased number of dead birds.
For more information on West Nile virus, visit www.ph.lacounty.gov/WestNileVirus.
