08/29/2025
FOR IMMEDIATE RELEASE | August 29, 2025
Public Health Reports First Human West Nile Virus Death of the Season
BUTTE COUNTY, Calif. – The Butte County Department of Public Health (BCPH) announced the first confirmed human case of West Nile Virus (WNV) on August 14. BCPH has now received confirmation that the individual, between 30 and 40 years old, died due to complications of their WNV illness. The individual developed a severe WNV illness with neurologic symptoms. BCPH extends its sincere condolences to the family and friends during this difficult time.
BCPH urges residents to protect themselves from WNV by reducing the number of mosquitoes on their property and preventing mosquito bites. Residents should take extra precautions as we head into the Labor Day weekend, at time when many people spend more time outdoors during peak mosquito biting hours which are dusk and dawn.
As of August 22, 17 human WNV infections have been confirmed in California. WNV is typically active from May through October, with August being the peak month in Butte County.
People infected with WNV generally fall into three categories:
• Asymptomatic (8 in 10 people)
• Mild to moderate fever illness with fatigue and body aches (1 in 5 people)
• Severe illness with neurologic symptoms such as encephalitis or meningitis (less than 1 in 150 people). For those who develop a severe WNV illness, symptoms may last several weeks and some symptoms may be permanent.
People 50 years of age and older, and individuals with diabetes or hypertension, have a higher chance of getting sick and are more likely to develop complications
WNV is transmitted to humans and animals by the bite of an infected mosquito. Mosquitoes become infected when they feed on infected birds. Residents can reduce the risk of infection by practicing the 3 Ds of prevention:
1. DEET – Use a proven insect repellent that includes DEET or look for EPA-registered repellents that contain one of the following active ingredients: picaridin, lemon eucalyptus oil, para-menthane-diol or IR3535. Always use according to label instructions. DEET can be used safely on infants and children 2 months of age and older.
2. DAWN AND DUSK – Mosquitoes that transmit WNV bite in the early morning and evening. Wear proper clothing and repellent if outside during these times. Make sure that doors and windows have tight-fitting screens to keep mosquitoes out. Repair or replace screens with tears or holes.
3. DRAIN – Mosquitoes lay their eggs on standing water. Eliminate or drain all sources of standing water on your property, including flower pots, old car tires, rain gutters and pet bowls. Mosquitoes can lay up to 300 larvae in one bottle cap of water. For standing water that cannot be drained such as fountains, ponds, etc., consider adding “Mosquito Dunks” or mosquito fish, which feed on mosquito larvae. Report unmaintained swimming pools to the local Mosquito and Vector Control District at (530) 342-7350 or (530) 533-6038.
WNV Resources:
• BCPH’s West Nile Virus Website (tinyurl.com/j6sejd83)
• California West Nile Virus Dashboard (westnile.ca.gov/)
• Butte County Mosquito and Vector Control District (www.buttemosquito.com/)
# # #
