Dead Birds Reported, Tested, and Positive
for WNV by County in California in 2017
Year To Date (Weeks 1 - 38)

(2017-09-22) - Source: http://www.westnile.ca.gov

CountyReported*TestedPositive% Tested Positive
Alameda2133413%
Alpine1---
Amador11---
Butte7921419%
Calaveras7---
Colusa82150%
Contra Costa536291034%
Del Norte----
El Dorado641616%
Fresno1509556%
Glenn622100%
Humboldt911100%
Imperial2---
Inyo9---
Kern7133100%
Kings273133%
Lake3319316%
Lassen----
Los Angeles7191095954%
Madera243133%
Marin518--
Mariposa4---
Mendocino9---
Merced516117%
Modoc----
Mono2---
Monterey294125%
Napa355--
Nevada225120%
Orange5343544412%
Placer22911322%
Plumas1---
Riverside260542954%
Sacramento8233307523%
San Benito81--
San Bernardino228493776%
San Diego194762837%
San Francisco406117%
San Joaquin20940615%
San Luis Obispo243--
San Mateo3105212%
Santa Barbara275--
Santa Clara39266711%
Santa Cruz581318%
Shasta3522100%
Sierra1---
Siskiyou1---
Solano8216213%
Sonoma1122329%
Stanislaus18319632%
Sutter5117212%
Tehama9---
Trinity11--
Tulare7716850%
Tuolumne51--
Ventura971417%
Yolo157521223%
Yuba4015640%
State Totals6360161736723%

* 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