Case Counts by County

CountyDead birds
Alameda12
Alpine-
Amador-
Butte33
Calaveras-
Colusa3
Contra Costa4
Del Norte-
El Dorado2
Fresno1
Glenn4
Humboldt2
Imperial-
Inyo-
Kern1
Kings3
Lake5
Lassen-
Los Angeles12
Madera1
Marin3
Mariposa-
Mendocino-
Merced1
Modoc-
Mono-
Monterey-
Napa5
Nevada9
Orange25
Placer8
Plumas-
Riverside39
Sacramento61
San Benito-
San Bernardino4
San Diego107
San Francisco-
San Joaquin11
San Luis Obispo-
San Mateo8
Santa Barbara-
Santa Clara83
Santa Cruz-
Shasta10
Sierra-
Siskiyou-
Solano7
Sonoma4
Stanislaus13
Sutter16
Tehama-
Trinity2
Tulare22
Tuolumne-
Ventura6
Yolo48
Yuba6
Total581

WNV Activity by County
Printable Version
2015 | 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
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Compared to previous year and previous five-year average to date

As of Aug 28, 2015201520145Y AVG
Counties403632
Human cases8312554
Dead birds5811573751
Mosquito samples207324841702
Sentinel chickens174184151
YTD - Year to date corresponds to the same time last year or last five years.

- view all 2014 YTD activity -

WNV Reports

Weekly Report

08.28 Arbovirus Bulletin #26
08.28 2015 YTD WNV Activity Map
08.25 2015 US Arboviral Activity Update

Humans

08.28 2015 Human WNV Incidence Report
08.28 2003-2015 WNV Case Summary
03.09 2014 Human WNV Incidence Report

Dead Birds

08.28Positive Species for 2015
08.28Positive Counts by City/County for 2015
08.28Reported, Tested, Positive 2015

Mosquitoes

08.28 AMOR - EVS Week 33
08.28 AMOR - GRAVID Week 33
08.28 AMOR - NJLT Week 33
- view report archives -