Human Cases
Year-to-date: 153 Counties: 25
There were 29 new WNV positive human cases reported in California last week from the following counties: Butte (1), Fresno (2), Glenn (1), Los Angeles (2), Madera (3), Merced (1), Sacramento (7), San Bernardino (2), San Joaquin (1), Shasta (2), Stanislaus (5), and Yolo (2). This is the first WNV positive human case from Fresno County this year.
6 WNV-related fatalities have been reported to CDPH this year from 5 counties:Lake (1), Los Angeles (1), Sacramento (1), San Bernardino (2), Yolo (1).
153 human cases from 25 counties have tested positive for WNV in 2023.
Dead Birds
Year-to-date: 654 Counties: 29
There were 87 new WNV positive dead birds reported in California last week from the following counties: Alameda (18), Contra Costa (9), El Dorado (1), Lake (3), Los Angeles (6), Placer (1), Riverside (10), Sacramento (12), San Benito (1), San Bernardino (1), San Diego (2), Santa Clara (16), Sonoma (1), and Yolo (6). This is the first WNV positive dead bird from San Benito County this year.
654 dead birds from 29 counties have tested positive for WNV in 2023.
Mosquito Samples
Year-to-date: 3,983 Counties: 30
There were 251 new WNV positive mosquito samples reported in California last week from the following counties: Alameda (4), Butte (1), Contra Costa (2), Fresno (12), Kern (7), Kings (9), Los Angeles (46), Madera (12), Merced (4), Napa (1), Orange (21), Placer (5), Riverside (37), Sacramento (6), San Bernardino (15), San Joaquin (15), Shasta (7), Stanislaus (17), Tulare (25), and Yolo (5).
3,983 mosquito samples from 30 counties have tested positive for WNV in 2023.
A mosquito sample may contain up to 50 individual mosquitoes.
Sentinel Chickens
Year-to-date: 155 Counties: 17
There were 8 new WNV positive sentinel chickens reported in California last week from the following counties: Butte (1), Calaveras (1), Contra Costa (2), Sutter (2), and Yolo (2).
155 sentinel chickens from 17 counties have tested positive for WNV in 2023.
Horses
Year-to-date: 21 Counties: 17
21 horses from 17 counties have tested positive for WNV in 2023.