Dead Birds Reported, Tested, and Positive
for WNV by County in California in 2020
Year To Date (Weeks 1 - 27)

(2020-07-06) - Source: http://www.westnile.ca.gov

CountyReported*TestedPositive% Tested Positive
Alameda12421--
Alpine----
Amador2---
Butte316--
Calaveras1---
Colusa1---
Contra Costa15117--
Del Norte----
El Dorado134--
Fresno1228338%
Glenn1---
Humboldt21--
Imperial----
Inyo----
Kern6---
Kings8---
Lake44--
Lassen----
Los Angeles2694736%
Madera5---
Marin9---
Mariposa----
Mendocino1---
Merced353133%
Modoc----
Mono----
Monterey123--
Napa83133%
Nevada8---
Orange14130--
Placer6231--
Plumas----
Riverside839--
Sacramento33813286%
San Benito1---
San Bernardino375--
San Diego7837--
San Francisco203--
San Joaquin781616%
San Luis Obispo8---
San Mateo9925--
Santa Barbara5---
Santa Clara2608256%
Santa Cruz4412--
Shasta13---
Sierra----
Siskiyou----
Solano235--
Sonoma344--
Stanislaus1218450%
Sutter142--
Tehama2---
Trinity----
Tulare334--
Tuolumne11--
Ventura227--
Yolo6823--
Yuba101--
State Totals2408554265%

* Birds in a die-off are not included in reported totals because the deaths are not related to WNV. A die-off is defined as a group of 10 or more same species dead birds unless the species is American Crow.
Source: Vector-Borne Disease Section, California Department of Public Health