First Detection of West Nile Virus in Los Angeles County
Collected dead birds tested positive for West Nile virus
Santa Fe Springs, CA (June 6, 2022) – The Greater Los Angeles County Vector Control District (GLACVCD/District) has confirmed the first detection of West Nile virus (WNV) activity in Los Angeles County. The virus was detected in three dead American crows collected in the neighborhood of North Hills (91343) on May 26th.
This confirmation serves as the District’s first detection of West Nile virus activity. Mosquito samples have not tested positive for the virus within the surrounding community, nor in Los Angeles County. The dead bird surveillance program serves as an early warning detection tool that helps identify when the virus is actively being transmitted within the bird population. The three dead birds were collected, shipped, and tested at the UC Davis Arbovirus Research and Training Laboratory which provides testing for multiple vector control agencies across the state.
“American crows can fly up to 40 miles each day from overnight roosting sites, so while there has not yet been virus activity detected in mosquito populations in Los Angeles County, this confirmation serves as an alert that mosquitoes may soon become infected and residents should take precautions,” said Director of Scientific-Technical Services Steve Vetrone.
Since West Nile virus is endemic to Los Angeles County, it is typically detected by local public health agencies during summer. Because there is no human vaccine for WNV, residents must be proactive against mosquito bites by wearing insect repellent. The Centers for Disease Control and Prevention recommend products with the active ingredients DEET, Picaridin, IR3535, or oil of lemon eucalyptus as being safe and effective against mosquitoes that can transmit disease when used according to the labels.
One in five persons infected with the virus will exhibit symptoms. Symptoms can include fever, headache, body aches, nausea, or 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. If residents feel they are experiencing symptoms, it is strongly recommended to consult their primary care physician.
Mosquito control is a shared responsibility and residents must take an active role in reducing the threat of WNV in their neighborhoods by taking these additional steps:
- Eliminate standing water in clogged rain gutters, rain barrels, discarded tires, buckets, watering troughs or anything that holds water for more than a week.
- Ensure that swimming pools, spas, and ponds are properly maintained.
- Change the water in pet dishes, bird baths and other small containers weekly.
- Request mosquitofish from your local vector control district for placement in ornamental ponds.
- Report neglected (green) swimming pools in your neighborhood to your vector control district.
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, Twitter, Instagram.
Anais Medina Diaz, Public Information Officer | amedinadiaz@GLAmosquito.org
Mary-Joy Coburn, Director of Communications | mjcoburn@GLAmosquito.org