Case Counts by County

CountyDead birds
Alameda-
Alpine-
Amador-
Butte-
Calaveras-
Colusa-
Contra Costa1
Del Norte-
El Dorado-
Fresno-
Glenn-
Humboldt-
Imperial-
Inyo-
Kern-
Kings-
Lake-
Lassen-
Los Angeles1
Madera-
Marin-
Mariposa-
Mendocino-
Merced-
Modoc-
Mono-
Monterey-
Napa-
Nevada-
Orange-
Placer-
Plumas-
Riverside-
Sacramento2
San Benito-
San Bernardino-
San Diego-
San Francisco-
San Joaquin-
San Luis Obispo-
San Mateo-
Santa Barbara-
Santa Clara1
Santa Cruz-
Shasta-
Sierra-
Siskiyou-
Solano-
Sonoma-
Stanislaus-
Sutter-
Tehama-
Trinity-
Tulare-
Tuolumne-
Ventura-
Yolo-
Yuba-
Total5

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

Human data is updated every Tuesday and Friday by 4pm. Dead bird and squirrel data are updated every Wednesday by 4pm. Horse, mosquito and sentinel chicken data are updated on Fridays by 4pm.
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Total Counties with
WNV in 2012: 5

Contra Costa, Los Angeles, Riverside, Sacramento, and Santa Clara.

Mosquito Control Matters video (MVCAC)
This video illustrates the importance of mosquito control and how we live, work and play in our communities would be drastically altered without it.

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human cases

YTD: 0 Counties: 0
No cases of human WNV illness have been reported positive for WNV in 2012.
 

horses

YTD: 0 Counties: 0
No horses have tested positive for WNV in 2012.
 

dead birds

YTD: 5 Counties: 4
[More info]
5 dead birds from 4 counties have tested positive for WNV in 2012.
 

mosquito samples

YTD: 1 Counties: 1
1 mosquito sample from 1 county has tested positive for WNV in 2012.
 

sentinel chickens

YTD: 0 Counties: 0
No sentinel chickens have tested positive for WNV in 2012.
 

squirrels

YTD: 0 Counties: 0
No squirrels have tested positive for WNV in 2012.

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2003-2011 WNV Activity Summary

Element 2003 2004 2005 2006 2007 2008 2009 2010 2011 Total
Human cases (fatal) 31 (0) 779 (29) 880 (19) 278 (7) 380 (21) 445 (15) 112 (4) 111 (6) 158 (9) 3,146 (110)
Horses 12 540 456 58 28 32 18 19 15 1,167
Dead birds 96 3,232 3,046 1,446 1,396 2,569 515 416 688 13,404
Mosquito samples 32 1,136 1,242 832 1,007 2,003 1063 1305 2,087 10,707
Sentinel chickens 70 809 1,053 640 510 585 443 281 391 4,782
Squirrels - 49 48 32 26 32 10 24 24 245
1 There were 20 imported human cases. 2 There were 3 imported horse cases.

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Compared to 2011 YTD

As of May 07, 201220112012
Counties55
Human cases00
Horses00
Dead birds65
Mosquito samples21
Sentinel chickens00
Squirrels00
2011 YTD - Year to date corresponds to the same time last year.

- view all 2011 YTD activity -

WNV Reports

Weekly Report

05.11 Arbovirus Bulletin #12
05.07 Arbovirus Bulletin #11
05.07 2012 YTD WNV Activity Map

Humans

04.26 2011 Human WNV Case Linelist
04.26 2011 Human WNV Incidence Report
04.26 2003-2011 WNV Case Summary

Dead Birds

05.07Positive Species for 2012
05.07Reported, Tested, Positive 2012 YTD
05.07Positive Counts by City/County for 2012

Mosquitoes

05.11 AMOR - EVS Week 18
05.11 AMOR - GRAVID Week 18
05.11 AMOR - NJLT Week 18

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 -