Health officials have confirmed human cases and positive mosquito samples of West Nile Virus (WNV) in Merced and Stanislaus counties, signaling early-season activity in California’s Central Valley. Merced County has already reported two human cases and a positive mosquito pool, while Stanislaus County has confirmed one case and positive samples collected by local abatement districts.

West Nile Virus spreads through the bite of infected mosquitoes, which become carriers after feeding on infected birds. While most people infected show no symptoms, about 1 in 5 may experience fever, headache, joint pain, or rash. In rare cases, the virus can cause serious neurological illness like meningitis or encephalitis, particularly in older adults or those with preexisting conditions.

There is no cure or vaccine for WNV — prevention is the best defense.
Residents are urged to:
• Dump standing water to prevent mosquito breeding.
• Use insect repellent with DEET, Picaridin, or Oil of Lemon Eucalyptus.
• Limit outdoor activity at dawn and dusk.
• Use tight-fitting screens on windows and doors.
• Report mosquito activity or neglected pools to your local abatement district.
• Vaccinate horses against WNV.

Los Angeles County residents should remain alert. West Nile virus is endemic throughout California, and local outbreaks often begin with bird or mosquito surveillance. To report dead birds statewide, call 1-877-WNV-BIRD or visit www.westnile.ca.gov.

Even small actions — like tipping a birdbath or wearing repellent — can help protect your family and community.