2019 SLEV Activity by County

(2025-10-23) - Source: http://westnile.ca.gov

CountyHuman CasesMosquito SamplesSentinel Chickens
State Totals63563
Alameda---
Alpine---
Amador---
Butte---
Calaveras---
Colusa---
Contra Costa---
Del Norte---
El Dorado---
Fresno258-
Glenn---
Humboldt---
Imperial25-
Inyo---
Kern156-
Kings-4-
Lake---
Lassen---
Los Angeles-2-
Madera-5-
Marin---
Mariposa---
Mendocino---
Merced-23
Modoc---
Mono---
Monterey---
Napa---
Nevada---
Orange-3-
Placer---
Plumas---
Riverside-108-
Sacramento---
San Benito---
San Bernardino-4-
San Diego---
San Francisco---
San Joaquin---
San Luis Obispo---
San Mateo---
Santa Barbara---
Santa Clara---
Santa Cruz---
Shasta---
Sierra---
Siskiyou---
Solano---
Sonoma---
Stanislaus113-
Sutter---
Tehama---
Trinity---
Tulare-96-
Tuolumne---
Ventura---
Yolo---
Yuba---
State Totals63563