West Nile Virus ActivityConfirmed Casesin California 2010 YTD vs 2009 YTD As of 7/7/10 Source:http://www.westnile.ca.gov | ||
| (2010 YTD-Year to date corresponds to the same time last year) |
2009 YTD | 2010 YTD |
| # of Counties | 25 | 17 |
| Human Cases | 0 | 0 |
| Horses | 0 | 0 |
| Dead Birds | 139 | 52 |
| Mosquito Samples | 97 | 48 |
| Sentinel Chickens | 5 | 0 |
| Squirrels | 1 | 1 |
| As of July 8, 2010, Alameda County has 6 cases of WNV in dead birds; no human WNV cases. | ||
What is West Nile Virus?
West Nile virus (WNV) is a potentially serious illness. Experts believe WNV is established as a seasonal epidemic in North America that flares up in the summer and continues into the fall. WNV season runs June 1-Nov. 1.
How WNV IS Spread to Humans?
WNV virus is transmitted to humans and animals through a mosquito bite. Mosquitos become infected when they feed on infected birds. Human-to-human transmission of WNV does not occur. However, human WNV infections have been associated with blood transfusions and organ transplants.
Control Activities in Alameda County
West Nile Virus activity in California was mild in 2009. Alameda County had no human cases of WNV in 2009 and only 10 birds were WNV positive. During WNV season, Alameda County’s Mosquito Abatement program works to limit risks to residents by monitoring ponds and other possible mosquito breeding sites; trapping to detect high numbers of mosquitoes; treating sewer catch-basins to prevent breeding; collecting birds for testing; and educating residents and owners about removing standing water from private property to limit mosquito breeding and mosquito bites.