Case Counts by County

CountyDead birds
Alameda96
Alpine-
Amador-
Butte22
Calaveras-
Colusa4
Contra Costa44
Del Norte-
El Dorado7
Fresno9
Glenn4
Humboldt2
Imperial-
Inyo-
Kern3
Kings3
Lake18
Lassen-
Los Angeles99
Madera5
Marin6
Mariposa-
Mendocino-
Merced8
Modoc-
Mono-
Monterey-
Napa12
Nevada-
Orange431
Placer40
Plumas-
Riverside1
Sacramento294
San Benito-
San Bernardino17
San Diego35
San Francisco-
San Joaquin53
San Luis Obispo-
San Mateo20
Santa Barbara2
Santa Clara925
Santa Cruz1
Shasta6
Sierra-
Siskiyou-
Solano33
Sonoma37
Stanislaus47
Sutter19
Tehama-
Trinity-
Tulare40
Tuolumne-
Ventura7
Yolo71
Yuba16
Total2437

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 Dec 16, 2014201420135Y AVG
Counties404440
Human cases794375241
Dead birds24371251901
Mosquito samples334025281966
Sentinel chickens443485428
YTD - Year to date corresponds to the same time last year or last five years.

- view all 2013 YTD activity -

WNV Reports

Weekly Report

12.16 2014 US Arboviral Activity Update
12.16 2014 YTD WNV Activity Map
12.12 Arbovirus Bulletin #42

Humans

12.16 2014 Human WNV Incidence Report
12.16 2003-2014 WNV Case Summary
08.12 2013 Human WNV Incidence Report

Dead Birds

12.16Reported, Tested, Positive 2014
12.16Positive Counts by City/County for 2014
12.16Positive Species for 2014

Mosquitoes

11.07 AMOR - EVS Week 44
11.07 AMOR - GRAVID Week 44
11.07 AMOR - NJLT Week 44
- view report archives -