First human West Nile virus infection confirmed in Northern California
AI-generated summary reviewed by our newsroom.
- Butte County confirmed Northern California’s first human West Nile case of 2025.
- This marks the 15th statewide infection, with one fatality reported so far.
- Officials urge mosquito bite prevention as peak virus season continues through October.
Northern California’s first human West Nile virus case of the year has been confirmed in Butte County, according to local health officials.
The Butte County Department of Public Health announced the infection in a news release Thursday afternoon, marking the 15 infection in the state this year. The infected person in Butte County, which is roughly 80 miles north of Sacramento, is between 30 to 40 years old and experiencing a severe case.
Of the 15 human cases this year, only one has led to a fatality, according to a dashboard from the California Department of Public Health. Last year, the state reported 13 human cases.
The virus is typically active from May through October and August is the peak month in Butte County, per the news release. People are recommended to prevent infections by reducing the number of mosquitoes on their property and preventing mosquito bites.
Further resources and tips on the virus can be found on California’s West Nile Dashboard website.
This story was originally published August 15, 2025 at 11:48 AM with the headline "First human West Nile virus infection confirmed in Northern California."
