Human data is updated every Tuesday by 4pm. Dead bird and squirrel data are updated every Wednesday by 4pm. Horse, mosquito and sentinel chicken data are updated either on Mondays or Fridays by 4pm.

- View Printable Map - Total Counties with WNV in 2010: 30 New counties highlighted in red. Amador, Butte, Colusa, Contra Costa, El Dorado, Fresno, Glenn, Imperial, Kern, Kings, Lake, Los Angeles, Madera, Merced, Orange, Placer, Riverside, Sacramento, San Bernardino, San Diego, San Joaquin, San Mateo, Santa Clara, Santa Cruz, Shasta, Stanislaus, Sutter, Tulare, Yolo, and Yuba. WNV News CDPH REPORTS FIRST HUMAN WEST NILE VIRUS CASES OF 2010 SACRAMENTO - Two women in Stanislaus County are the first confirmed human cases of West Nile virus (WNV) infection in California this year. The women were identified after they donated blood and routine testing performed by the blood bank confirmed WNV infection. - view news and press release archives - National Activity As of August 24, 2010, 144 human cases of WNV had been reported nationwide in 21 states: Alabama (1), Arizona (54), California (22), Colorado (10), Florida (1), Georgia (4), Kansas (2), Louisiana (7), Maryland (2), Michigan (2), Minnesota (2), Mississippi (3), Missouri (1), Nebraska (8), New York (10), North Dakota (4), Ohio (1), Pennsylvania (1), South Dakota (5), Texas (3), and Wyoming (1). Of the 144 cases, 70 (49%) had neuroinvasive disease. Three WNV-related fatalities have been reported in Arizona.

human cases YTD: 34 Counties: 10 There were 7 new WNV positive human cases reported in California this week from the following counties: Fresno (3), Placer (1), Sacramento (2), and San Joaquin (1). These are the first WNV positive human cases from Placer and San Joaquin counties this year. 34 human cases from 10 counties have tested positive for WNV in 2010.   horses YTD: 11 Counties: 8 There were 3 new WNV positive horses reported in California this week from the following counties: Amador (1), Fresno (1), and Kern (1). These are the first WNV positive horses from Fresno and Kern counties this year. This is the first indication of WNV from Amador County this year. 11 horses from 8 counties have tested positive for WNV in 2010.   dead birds YTD: 285 Counties: 23 There were 25 new WNV positive dead birds reported in California this week from the following counties: Butte (1), El Dorado (2), Fresno (5), Los Angeles (3), Merced (1), Placer (1), Sacramento (2), San Bernardino (1), San Joaquin (3), Stanislaus (3), Tulare (2), and Yolo (1). This is the first indication of WNV from El Dorado County this year. [More info] 285 dead birds from 23 counties have tested positive for WNV in 2010.   mosquito samples YTD: 919 Counties: 23 There were 135 new WNV positive mosquito samples reported in California last week from the following counties: Butte (1), Fresno (9), Kern (35), Kings (10), Los Angeles (6), Madera (2), Orange (1), Placer (8), Riverside (1), Sacramento (13), San Bernardino (8), San Joaquin (13), Stanislaus (4), Sutter (3), Tulare (20), and Yuba (1). 919 mosquito samples from 23 counties have tested positive for WNV in 2010.   sentinel chickens YTD: 93 Counties: 14 There were 15 new WNV positive sentinel chickens reported in California last week from the following counties: Butte (1), Colusa (1), Los Angeles (1), Stanislaus (5), Sutter (5), Tulare (1), and Yuba (1). These are the first WNV positive sentinel chickens from Butte and Yuba counties this year. 93 sentinel chickens from 14 counties have tested positive for WNV in 2010.   squirrels YTD: 13 Counties: 7 There have been 2 new WNV positive squirrels reported in California this week from San Mateo (1) and Santa Clara (1) counties. 13 squirrels from 7 counties have tested positive for WNV in 2010.

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