[Mike]

West Nile Virus Now
Rampant In California
From Patricia Doyle, PhD
dr_p_doyle@…
9-15-5

West Nile Virus in California
In 2005:
53 counties have reported WNV activity in California this year.
618 individuals from 36 counties have been infected with WNV in 2005.
To date in 2005, there have been nine WNV-related fatalities.
349 horses* have tested positive for WNV in 38 counties, of these 149 have died or been euthanized.
2,219 dead birds in 50 counties have tested positive for WNV.
1,049 mosquito pools** from 28 counties have tested positive for WNV.
705 sentinel chickens from 30 counties have tested positive for West Nile/Saint Louis Encephalitis (SLE)*** antibodies.
Click here for more on the Latest West Nile Virus Activity in California
Latest Activity 09/13/05
West Nile virus activity was detected in all 58 California Counties in 2004
West Nile virus activity has been detected in 53 California counties in 2005 .
Humans
To date in 2005, there have been 618 human WNV infections from 36 counties in California.
75 of the 618 infections were first detected in asymptomatic individuals through screening done at blood banks – 32later became symptomatic.
Four asymptomatic individuals were detected via local public health agencies.
Of the 571 WNV cases with symptoms, 191 are classified as West Nile neuroinvasive disease, 329 are classified as West Nile fever cases, and 51 are of unknown clinical presentation.
There have been nine West Nile virus-related fatalities to date in California this year from Butte, Fresno, Kings, Riverside, Sacramento, and San Joaquin counties.
Horses *
28 WNV horse cases from 20 counties were reported this week by the California Department of Food and Agriculture, including the first WNV horse infection in Mono County in 2005.
In 2005, 349 horses from 38 counties have been infected with WNV. Of the horses with infections, 149 have either died or been euthanized.
Dead Birds
251 dead birds from 36 counties tested positive for WNV this week.
In 2005, 2,219 dead birds from 50 counties have tested positive for WNV in California.
Mosquito Pools and Sentinel Chickens
47 mosquito pools** from 11 counties tested positive for WNV this week.
In 2005, 1,049 mosquito pools from 28 counties have tested positive for WNV.
705 chickens from 30 counties have tested positive for WNV/SLE ***antibodies (seroconverted) in 2005.
* Horse data is only updated on Fridays
** A mosquito pool is a collection of approximately 50 mosquitoes that are tested together for West Nile virus.
*** WNV and SLE (St. Louis encephalitis) are closely related viruses in the family Flaviviridae and preliminary testing cannot distinguish between these two viruses. Further testing is conducted as needed to determine if the sentinel chickens are antibody positive to WNV or SLE.
2005 California Map Of WNV Activity
http://www.westnile.ca.gov/2005_maps.htm
http://www.westnile.ca.gov/