Case Counts by County

CountyDead birds
Alameda2
Alpine-
Amador-
Butte1
Calaveras-
Colusa-
Contra Costa-
Del Norte-
El Dorado1
Fresno-
Glenn1
Humboldt-
Imperial-
Inyo-
Kern-
Kings1
Lake-
Lassen-
Los Angeles2
Madera1
Marin1
Mariposa-
Mendocino-
Merced-
Modoc-
Mono-
Monterey-
Napa-
Nevada-
Orange1
Placer-
Plumas-
Riverside5
Sacramento5
San Benito-
San Bernardino-
San Diego35
San Francisco-
San Joaquin1
San Luis Obispo-
San Mateo3
Santa Barbara-
Santa Clara22
Santa Cruz-
Shasta2
Sierra-
Siskiyou-
Solano1
Sonoma2
Stanislaus4
Sutter3
Tehama-
Trinity-
Tulare12
Tuolumne-
Ventura1
Yolo3
Yuba2
Total112

WNV Activity by County
Printable Version
2015 | 2014 | 2013
2012 | 2011 | 2010
2009 | 2008 | 2007

Human data is updated every Tuesday by 4pm. Dead bird data is updated every Wednesday and Friday by 4pm. Mosquito and sentinel chicken data are updated on Fridays by 4pm.

Due to different reporting schedules, case totals on this website may not always be consistent with those reported by local health departments.

Interactive Map

View the interactive map courtesy of http://maps.calsurv.org
- View Printable Map -

Total Counties with
WNV in 2015: 31

Alameda, Butte, Contra Costa, El Dorado, Fresno, Glenn, Kern, Kings, Los Angeles, Madera, Marin, Merced, Orange, Placer, Riverside, Sacramento, San Bernardino, San Diego, San Joaquin, San Mateo, Santa Barbara, Santa Clara, Shasta, Solano, Sonoma, Stanislaus, Sutter, Tulare, Ventura, Yolo, and Yuba.

human cases

YTD: 0 Counties: 0
No cases of human WNV illness have been reported positive for WNV in 2015.
 

dead birds

YTD: 112 Counties: 24
There were 11 new WNV positive dead birds reported in California last week from the following counties: Kings (1), Riverside (1), San Diego (2), Santa Clara (1), Sutter (1), Tulare (4), and Yuba (1). This is the first WNV positive dead bird from Kings County this year.

112 dead birds from 24 counties have tested positive for WNV in 2015.

 

mosquito samples

YTD: 240 Counties: 20
There were 60 new WNV positive mosquito samples reported in California last week from the following counties: Butte (2), Fresno (1), Kings (1), Los Angeles (1), Placer (5), Riverside (1), Sacramento (5), San Joaquin (25), Sutter (5), Tulare (10), and Yuba (4). These are the first WNV positive mosquito samples from Placer and Sutter counties this year.

240 mosquito samples from 20 counties have tested positive for WNV in 2015.

 

sentinel chickens

YTD: 3 Counties: 2

3 sentinel chickens from 2 counties have tested positive for WNV in 2015.

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2003-2014 WNV Activity Summary

Element 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 Total
Human cases (fatal) 31 (0) 779 (29) 880 (19) 278 (7) 380 (21) 445 (15) 112 (4) 111 (6) 158 (9) 479 (20) 379 (15) 801 (31) 4,805 (176)
Horses 12 540 456 58 28 32 18 19 15 22 13 03 1,202
Dead birds 96 3,232 3,046 1,446 1,396 2,569 515 416 688 1,644 1,251 2,442 18,741
Mosquito samples 32 1,136 1,242 832 1,007 2,003 1,063 1,305 2,087 2849 2,528 3,340 19,424
Sentinel chickens 70 809 1,053 640 510 585 443 281 391 540 485 443 6,250
Squirrels - 49 48 32 26 32 10 24 24 23 03 03 276
1 There were 20 imported human cases. 2 There were 3 imported horse cases. 3 No longer monitored.

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

As of Jul 02, 2015201520145Y AVG
Counties312118
Human cases021
Dead birds112325138
Mosquito samples240234144
Sentinel chickens311
YTD - Year to date corresponds to the same time last year or last five years.

- view all 2014 YTD activity -

WNV Reports

Weekly Report

07.02 Arbovirus Bulletin #18
07.02 2015 YTD WNV Activity Map
06.30 2015 US Arboviral Activity Update

Humans

04.02 2003-2014 WNV Case Summary
03.09 2014 Human WNV Incidence Report
08.12 2013 Human WNV Incidence Report

Dead Birds

07.02Positive Species for 2015
07.02Positive Counts by City/County for 2015
07.02Reported, Tested, Positive 2015

Mosquitoes

07.02 AMOR - EVS Week 25
07.02 AMOR - GRAVID Week 25
07.02 AMOR - NJLT Week 25
- view report archives -