Dead Birds Reported, Tested, and Positive
for WNV by County in California in 2020
Year To Date (Weeks 1 - 13)

(2020-04-02) - Source: http://www.westnile.ca.gov

CountyReported*TestedPositive% Tested Positive
Alameda38---
Alpine----
Amador----
Butte10---
Calaveras----
Colusa----
Contra Costa43---
Del Norte----
El Dorado5---
Fresno22---
Glenn----
Humboldt----
Imperial----
Inyo----
Kern1---
Kings2---
Lake----
Lassen----
Los Angeles594--
Madera1---
Marin5---
Mariposa----
Mendocino----
Merced7---
Modoc----
Mono----
Monterey3---
Napa2---
Nevada3---
Orange3727--
Placer2814--
Plumas----
Riverside11---
Sacramento95---
San Benito----
San Bernardino9---
San Diego1712--
San Francisco7---
San Joaquin14---
San Luis Obispo1---
San Mateo2811--
Santa Barbara----
Santa Clara5526312%
Santa Cruz232--
Shasta5---
Sierra----
Siskiyou----
Solano6---
Sonoma5---
Stanislaus15---
Sutter6---
Tehama2---
Trinity----
Tulare20---
Tuolumne----
Ventura31--
Yolo25---
Yuba3---
State Totals6169733%

* 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