West Nile Virus Update for September 2018
San Mateo County
As of September 28, 2018, there have been 330 dead birds reported in San Mateo County. Of those, 103 have been suitable for testing and five have tested positive (5%) for West Nile virus (WNV). Two mosquito pools have tested positive for WNV, both from East Palo Alto during the month of August. Positive birds and pools for 2018 are summarized in the tables below. No sentinel chickens have tested positive for West Nile Virus in San Mateo County in 2018.
The statewide dead bird hotline closes for the season on Friday October 12. However, the District asks residents to continue to report dead birds by contact the state WNV hotline at 877-WNV-BIRD (968-2473). Although there will not be live operators after the 12th, recorded messages with a brief description of the bird and location information will be forwarded to the District. Reports can also be made online at http://westnile.ca.gov. The District will test suitable birds on a limited basis during the winter season.
SEASONAL TOTALS OF WNV POSITIVE BIRDS – 2018
SEASONAL TOTALS OF WNV POSITIVE MOSQUITO POOLS – 2018
WNV has been detected in 37 counties in 2018 (see map) compared to a five year average of 40 counties at this date. Throughout California, there have been 114 human cases of WNV, including five fatalities, compared to a five-year average of 277 human cases at this date. Statewide, 6,918 dead birds have been reported and 1,849 have been tested with 469 positive results (25%). 1,889 mosquito pools have tested positive for WNV this year and 139 sentinel chickens have tested positive compared to a five-year average of 2,974 positive mosquito pools and 332 positive sentinel chickens. Overall, this is a lower than average year for West Nile Virus across the state, with the highest amount of activity in Sacramento and San Joaquin counties in the central valley.