The Fresno County Department of Public Health (FCDPH) has confirmed Fresno County’s first West Nile virus (WNV) human death of 2025. So far this year, the FCDPH has reported 5 additional positive human cases of WNV, and more cases are expected as the mosquito season can last through the end of October. Mosquitoes become infected with WNV when they bite infected birds. The infected mosquitoes can then bite and potentially infect humans and other animals.
According to the California Department of Public Health (CDPH) there have been 43 reported human WNV cases in California in 2025, including 2 other deaths. Since WNV was first identified in California in 2003, there have been more than 8,000 human WNV cases and more than 400 WNV-related deaths across the state.
“Our heartfelt condolences go out to the family and friends of this individual. We need to stay vigilant as mosquitoes may continue to test positive for WNV in the County. The infected mosquitoes may cause severe illnesses, including WNV infection, which can require hospitalization and can result in death,” says Dr. Rais Vohra, Fresno County Interim Health Officer. “It is very important that we take steps to minimize mosquito bites, especially when there is an increase in mosquito activity during these warmer temperatures.”
To reduce the risk of being bitten by mosquitoes and contracting WNV, Fresno County residents are urged to take the following precautions:
- Apply EPA-registered insect repellents that contain DEET, picaridin, oil of lemon eucalyptus, or IR 3535, especially at dawn and dusk when mosquitoes that can transmit WNV are most active.
- Make sure that doors and windows have tight-fitting screens to keep out mosquitoes and repair or replace screens that have holes.
- Eliminate standing water and containers that can hold water from around the home.
- Contact mosquito abatement districts to report poorly maintained swimming pools or water features that appear green.
Residents can also call their Mosquito Abatement District representative or visit www.fresnocountymosquito.org for more information on how to protect their family, their home, and their community from WNV and other mosquito borne illnesses.
