Dead Birds Reported, Tested, and Positive
for WNV by County in California in 2018
Year To Date (Weeks 1 - 29)

(2018-07-22) - Source: http://www.westnile.ca.gov

CountyReported*TestedPositive% Tested Positive
Alameda19122836%
Alpine----
Amador131--
Butte4510--
Calaveras4---
Colusa51--
Contra Costa26213--
Del Norte21--
El Dorado3811218%
Fresno1151--
Glenn1---
Humboldt174125%
Imperial1---
Inyo1---
Kern28---
Kings72--
Lake113--
Lassen----
Los Angeles4853426%
Madera102--
Marin24---
Mariposa----
Mendocino2---
Merced361--
Modoc----
Mono----
Monterey242--
Napa142--
Nevada101--
Orange251185--
Placer2096223%
Plumas1---
Riverside10114214%
Sacramento6252336729%
San Benito51--
San Bernardino8513--
San Diego10048--
San Francisco241--
San Joaquin1021318%
San Luis Obispo122--
San Mateo2276623%
Santa Barbara153--
Santa Clara3631051312%
Santa Cruz922614%
Shasta8---
Sierra1---
Siskiyou----
Solano585--
Sonoma635--
Stanislaus984125%
Sutter367--
Tehama91--
Trinity2---
Tulare406--
Tuolumne3---
Ventura589--
Yolo9025624%
Yuba2511--
State Totals404995610811%

* 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