Case Counts by County

CountyDead birds
Alameda60
Alpine-
Amador-
Butte18
Calaveras-
Colusa4
Contra Costa27
Del Norte-
El Dorado1
Fresno8
Glenn4
Humboldt2
Imperial-
Inyo-
Kern3
Kings2
Lake14
Lassen-
Los Angeles30
Madera4
Marin3
Mariposa-
Mendocino-
Merced-
Modoc-
Mono-
Monterey-
Napa9
Nevada-
Orange189
Placer23
Plumas-
Riverside-
Sacramento232
San Benito-
San Bernardino8
San Diego4
San Francisco-
San Joaquin36
San Luis Obispo-
San Mateo8
Santa Barbara-
Santa Clara690
Santa Cruz1
Shasta2
Sierra-
Siskiyou-
Solano31
Sonoma13
Stanislaus31
Sutter19
Tehama-
Trinity-
Tulare38
Tuolumne-
Ventura2
Yolo43
Yuba11
Total1570

WNV Activity by County
Printable Version
2014 | 2013 | 2012
2011 | 2010 | 2009
2008 | 2007

News

West Nile Virus Activity Increases in California

Jul 5, 2007

As of July 5, 25 counties have detected West Nile Virus (WNV) activity. Three human WNV cases have been reported in Kern County and two equine cases in Sonoma County.

Surveillance for WNV in 2007 has identified 159 West Nile Virus positive dead birds from 20 counties, four flocks of WNV positive sentinel chickens in three counties and 72 WNV positive mosquito pools from nine counties. These surveillance numbers could indicate that the mosquito and vector control agencies may have another busy year battling WNV carrying mosquitoes.

The public is urged to follow the three "Ds" to help protect themselves and their families from WNV:

  • To help protect yourself and others use repellents that contain DEET, Picaridin or oil of lemon eucalyptus before going outdoors.

  • Fix or replace missing or torn door and window screens to keep mosquitoes out of your home. Offer to help neighbors fix their screens.

  • DRAIN standing water in and around your yard so mosquitoes will not have a place to lay their eggs. Change water in pet dishes, birdbaths, plants and flower containers weekly. Keep gutters free from leaves and debris. Help others in your neighborhood to "mosquito proof" their yards, too.

Locate Your Local Mosquito and Vector Control Agency
Search by Zip Code

Compared to previous year and previous five-year average to date

As of Aug 22, 2014201420135Y AVG
Counties363932
Human cases935933
Dead birds1570834508
Mosquito samples230815621175
Sentinel chickens184231142
YTD - Year to date corresponds to the same time last year or last five years.

- view all 2013 YTD activity -

WNV Reports

Weekly Report

08.22 Arbovirus Bulletin #27
08.22 2014 YTD WNV Activity Map
08.19 2014 US Arboviral Activity Update

Humans

08.18 2014 Human WNV Incidence Report
08.18 2003-2014 WNV Case Summary
08.12 2013 Human WNV Incidence Report

Dead Birds

08.22Reported, Tested, Positive 2014
08.22Positive Counts by City/County for 2014
08.22Positive Species for 2014

Mosquitoes

08.22 AMOR - EVS Week 33
08.22 AMOR - GRAVID Week 33
08.22 AMOR - NJLT Week 33

Horses

12.16 2010 Equine WNV Result Map
12.16 2010 Confirmed Equine Cases Report
05.26 2009 Equine WNV Result Map
- view report archives -