2020 WNV Activity by County

(2022-12-03) - Source: http://westnile.ca.gov

Total Positive Counties: 40

CountyHuman CasesDead BirdsMosquito SamplesSentinel ChickensHorses
State Totals235343262814420
Alameda-8---
Alpine-1---
Amador----2
Butte4428231
Calaveras---2-
Colusa-----
Contra Costa422137-
Del Norte-----
El Dorado1----
Fresno105322--
Glenn1-321
Humboldt-----
Imperial1-3--
Inyo-----
Kern8-83--
Kings2-87-1
Lake2-122-
Lassen-----
Los Angeles9010243738-
Madera6-77--
Marin-1---
Mariposa-----
Mendocino-----
Merced12242141
Modoc----1
Mono-----
Monterey-----
Napa-12--
Nevada----1
Orange1747326--
Placer2358--
Plumas-----
Riverside10264-2
Sacramento79111541
San Benito---1-
San Bernardino3-13-1
San Diego112--
San Francisco-----
San Joaquin24260-4
San Luis Obispo-----
San Mateo-1---
Santa Barbara--1--
Santa Clara-78--
Santa Cruz-----
Shasta2-253-
Sierra-----
Siskiyou-----
Solano13841
Sonoma-----
Stanislaus354351-3
Sutter1-2026-
Tehama2--5-
Trinity-----
Tulare7518910-
Tuolumne-----
Ventura---1-
Yolo429771-
Yuba--21-
State Totals235343262814420