Human Cases
Year-to-date: 99 Counties: 21
There were 7 new WNV positive human cases reported in California this week from the following counties: Fresno (2), Kern (1), Los Angeles (3), and Solano (1). This is the first WNV positive human case from Solano County this year.
9 WNV-related fatalities have been reported to CDPH this year from 8 jurisdictions: Butte (1), Fresno (2), Kings (1), Los Angeles (1), Placer (1), San Joaquin (1), Santa Clara (1), and Tulare (1).
99 human cases from 21 counties have tested positive for WNV in 2025.
Dead Birds
Year-to-date: 152 Counties: 21
There was 1 new WNV positive dead bird reported in California this week from San Diego County.
152 dead birds from 21 counties have tested positive for WNV in 2025.
Mosquito Samples
Year-to-date: 2,755 Counties: 27
There were 5 new WNV positive mosquito samples reported in California this week from the following counties: Los Angeles (3), San Bernardino (1), and San Diego (1).
2,755 mosquito samples from 27 counties have tested positive for WNV in 2025.
A mosquito sample may contain up to 50 individual mosquitoes.
Sentinel Chickens
Year-to-date: 64 Counties: 8
There was 1 new WNV positive sentinel chicken reported in California this week from Los Angeles County.
64 sentinel chickens from 8 counties have tested positive for WNV in 2025.
Horses
Year-to-date: 5 Counties: 5
5 horses from 5 counties have tested positive for WNV in 2025.