Dead Birds Reported, Tested, and Positive
for WNV by County in California in 2014
Year To Date (Weeks 1 - 53)

(2024-10-13) - Source: http://westnile.ca.gov

CountyReported*TestedPositive% Tested Positive
Alameda9111669658%
Alpine1---
Amador19---
Butte181452249%
Calaveras16---
Colusa156467%
Contra Costa13551144439%
Del Norte11--
El Dorado12936719%
Fresno30212975%
Glenn108450%
Humboldt214250%
Imperial1---
Inyo2---
Kern824375%
Kings2933100%
Lake102431842%
Lassen----
Los Angeles16421559964%
Madera3610550%
Marin15016638%
Mariposa3---
Mendocino30---
Merced12812867%
Modoc1---
Mono3---
Monterey506--
Napa117131292%
Nevada4711--
Orange126268543163%
Placer3731624025%
Plumas4---
Riverside1411517%
Sacramento173553529455%
San Benito181--
San Bernardino238361747%
San Diego3101503926%
San Francisco924--
San Joaquin377945356%
San Luis Obispo32---
San Mateo5021472114%
Santa Barbara347229%
Santa Clara3950109792584%
Santa Cruz1533413%
Shasta8410660%
Sierra----
Siskiyou6---
Solano357483369%
Sonoma559593763%
Stanislaus445714766%
Sutter104431944%
Tehama19---
Trinity4---
Tulare156584069%
Tuolumne8---
Ventura14438718%
Yolo3791167161%
Yuba66301653%
State Totals169364105244259%

* 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