Dead Birds Reported, Tested, and Positive
for WNV by County in California in 2015
Year To Date (Weeks 1 - 53)

(2017-12-15) - Source: http://www.westnile.ca.gov

CountyReported*TestedPositive% Tested Positive
Alameda509821923%
Alpine----
Amador14---
Butte322823846%
Calaveras18---
Colusa164375%
Contra Costa915491122%
Del Norte31--
El Dorado13626415%
Fresno18710330%
Glenn165480%
Humboldt339222%
Imperial3---
Inyo3---
Kern5811100%
Kings227343%
Lake6021524%
Lassen6---
Los Angeles120916410363%
Madera163133%
Marin17214321%
Mariposa9---
Mendocino20---
Merced11413323%
Modoc7---
Mono9---
Monterey375--
Napa7711764%
Nevada55171059%
Orange6744278319%
Placer3611922111%
Plumas4---
Riverside3581108275%
Sacramento106336310328%
San Benito162--
San Bernardino281412561%
San Diego98055035565%
San Francisco10915--
San Joaquin301681826%
San Luis Obispo411--
San Mateo6871582315%
Santa Barbara718338%
Santa Clara157535723165%
Santa Cruz14043--
Shasta132261662%
Sierra----
Siskiyou5---
Solano177141071%
Sonoma283361131%
Stanislaus323441432%
Sutter102431637%
Tehama27---
Trinity116233%
Tulare137442352%
Tuolumne112--
Ventura254362672%
Yolo3131246149%
Yuba5416638%
State Totals125363250134942%

* 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