Case Counts by County

CountyDead birds
Alameda64
Alpine-
Amador-
Butte18
Calaveras-
Colusa4
Contra Costa30
Del Norte-
El Dorado1
Fresno8
Glenn4
Humboldt2
Imperial-
Inyo-
Kern3
Kings2
Lake15
Lassen-
Los Angeles35
Madera4
Marin3
Mariposa-
Mendocino-
Merced1
Modoc-
Mono-
Monterey-
Napa9
Nevada-
Orange228
Placer27
Plumas-
Riverside-
Sacramento238
San Benito-
San Bernardino9
San Diego7
San Francisco-
San Joaquin40
San Luis Obispo-
San Mateo9
Santa Barbara-
Santa Clara769
Santa Cruz1
Shasta3
Sierra-
Siskiyou-
Solano32
Sonoma15
Stanislaus31
Sutter19
Tehama-
Trinity-
Tulare38
Tuolumne-
Ventura2
Yolo46
Yuba16
Total1733

WNV Activity by County
Printable Version
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.
- View Printable Map -

Total Counties with
WNV in 2014: 36

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

CDPH Reports First Human West Nile Virus Fatalities This Summer
SACRAMENTO - The first two deaths this summer due to West Nile virus infection have been confirmed by the California Department of Public Health (CDPH) it was announced today by Dr. Ron Chapman, CDPH Director and state public health officer. The first was a senior citizen from Sacramento County. The second was an adult from Shasta County.
- view news and press release archives -

NOTE:

human cases

YTD: 129 Counties: 19
There were 36 new WNV human cases reported in California last week from the following counties: Butte (3), Colusa (1), Fresno (2), Glenn (1), Los Angeles (9), Orange (10), San Bernardino (1), Stanislaus (6), Sutter (1), Tulare (1), and Yuba (1). This is the first WNV human case from Sutter County this year.

6 WNV-related fatalities have been reported in to CDPH from in 5 counties: Glenn (1), Sacramento (1), Shasta (1), Stanislaus (2), and Sutter (1).

129 human cases from 19 counties have tested positive for WNV in 2014.

 

dead birds

YTD: 1,733 Counties: 34
There were 163 new WNV positive dead birds reported in California last week from the following counties: Alameda (4), Contra Costa (3), Lake (1), Los Angeles (5), Merced (1), Orange (39), Placer (4), Sacramento (6), San Bernardino (1), San Diego (3), San Joaquin (4), San Mateo (1), Santa Clara (79), Shasta (1), Solano (1), Sonoma (2), Yolo (3), and Yuba (5). This is the first WNV positive dead bird from Merced County this year.

1,733 dead birds from 34 counties have tested positive for WNV in 2014.

 

mosquito samples

YTD: 2,485 Counties: 29
There were 180 new WNV positive mosquito samples reported in California last week from the following counties: Contra Costa (3), Fresno (14), Kern (9), Lake (2), Los Angeles (21), Madera (4), Placer (4), Riverside (22), Sacramento (37), San Bernardino (7), San Joaquin (18), San Mateo (1), Santa Clara (1), Shasta (6), Stanislaus (9), Sutter (1), Tulare (7), Yolo (13), and Yuba (1).

2,485 mosquito samples from 29 counties have tested positive for WNV in 2014.

 

sentinel chickens

YTD: 242 Counties: 20
There were 58 new WNV positive sentinel chickens reported in California last week from the following counties: Los Angeles (39), Merced (3), Riverside (3), Sacramento (3), San Bernardino (3), Santa Clara (2), and Yolo (5). This is the first WNV positive sentinel chicken from Santa Clara County this year.

242 sentinel chickens from 20 counties have tested positive for WNV in 2014.

Be a West Nile Watcher

Help us track down the West Nile Virus by reporting all dead birds. You can submit an online report by clicking on the button on the right.

2003-2013 WNV Activity Summary

Element 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 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) 4,004 (145)
Horses 12 540 456 58 28 32 18 19 15 22 13 1,202
Dead birds 96 3,232 3,046 1,446 1,396 2,569 515 416 688 1,644 1,251 16,299
Mosquito samples 32 1,136 1,242 832 1,007 2,003 1,063 1,305 2,087 2849 2,528 16,084
Sentinel chickens 70 809 1,053 640 510 585 443 281 391 540 485 5,807
Squirrels - 49 48 32 26 32 10 24 24 23 8 276
1 There were 20 imported human cases. 2 There were 3 imported horse cases.

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 Aug 29, 2014201420135Y AVG
Counties364134
Human cases1298646
Dead birds1733907572
Mosquito samples248518541374
Sentinel chickens242267177
YTD - Year to date corresponds to the same time last year or last five years.

- view all 2013 YTD activity -

WNV Reports

Weekly Report

08.29 Arbovirus Bulletin #28
08.29 2014 YTD WNV Activity Map
08.26 2014 US Arboviral Activity Update

Humans

08.25 2014 Human WNV Incidence Report
08.25 2003-2014 WNV Case Summary
08.12 2013 Human WNV Incidence Report

Dead Birds

08.29Reported, Tested, Positive 2014
08.29Positive Counts by City/County for 2014
08.29Positive Species for 2014

Mosquitoes

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