Case Counts by County

CountyDead birds
Alameda13
Alpine-
Amador-
Butte2
Calaveras-
Colusa1
Contra Costa19
Del Norte-
El Dorado1
Fresno7
Glenn1
Humboldt1
Imperial-
Inyo-
Kern2
Kings1
Lake5
Lassen-
Los Angeles9
Madera4
Marin2
Mariposa-
Mendocino-
Merced-
Modoc-
Mono-
Monterey-
Napa5
Nevada-
Orange55
Placer16
Plumas-
Riverside-
Sacramento143
San Benito-
San Bernardino2
San Diego1
San Francisco-
San Joaquin23
San Luis Obispo-
San Mateo3
Santa Barbara-
Santa Clara429
Santa Cruz1
Shasta2
Sierra-
Siskiyou-
Solano27
Sonoma8
Stanislaus17
Sutter13
Tehama-
Trinity-
Tulare32
Tuolumne-
Ventura1
Yolo21
Yuba5
Total872

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 2013 YTD

As of Jul 23, 201420132014
Counties3235
Human cases415
Dead birds325872
Mosquito samples555771
Sentinel chickens2714
2013 YTD - Year to date corresponds to the same time last year.

- view all 2013 YTD activity -

WNV Reports

Weekly Report

07.25 2014 YTD WNV Activity Map
07.18 Arbovirus Bulletin #22
07.15 2014 US Arboviral Activity Update

Humans

07.21 2014 Human WNV Incidence Report
07.21 2003-2014 WNV Case Summary
04.21 2013 Human WNV Incidence Report

Dead Birds

07.25Reported, Tested, Positive 2014
07.25Positive Counts by City/County for 2014
07.25Positive Species for 2014

Mosquitoes

07.25 AMOR - EVS Week 29
07.25 AMOR - GRAVID Week 29
07.25 AMOR - NJLT Week 29

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 -