SACRAMENTO Heavy rains and warm temperatures have led to the early arrival of mosquitoes and West Nile virus (WNV) in California, State Public Health Officer Dr. Richard J. Jackson announced today. To date, WNV has been detected in 19 of Californias 58 counties. No human cases have yet been reported in 2005.
"This is a critical time for mosquito prevention," Jackson said. "Residents should eliminate standing water around their homes where mosquitoes might breed, keep their pools in good working order and report dead birds."
As of today, 32 dead birds from the following counties have tested positive for WNV: Alameda, Contra Costa, El Dorado, Fresno, Humboldt, Kern, Kings, Los Angeles, Orange, Placer, Sacramento, Santa Clara, Santa Cruz, Solano, Sonoma, Stanislaus, Tulare and Yolo counties. WNV has also been detected in a sentinel chicken in San Bernardino County and mosquitoes in Orange County.
"Early detection is the key to preventing the spread of West Nile virus," Jackson said. "We anticipate that there will be an increase in West Nile virus activity in Northern and Central California this year. "
Jackson also urged all horse owners to consult their veterinarians about proper and timely WNV vaccinations for their animals. In 2004, 540 equine WNV infections were reported statewide, most of which involved horses that were not vaccinated.
"Although California experienced widespread West Nile virus transmission last year, we believe that the number of human cases would have been greater without the aggressive control measures conducted by state and local agencies," Jackson said. "Personal protection measures taken by the public last year were significant in minimizing illness and death from West Nile virus. I urge all residents to be vigilant in avoiding mosquito bites."
Last year, there were a total of 829 human WNV infections, including 27 deaths, reported from 23 counties in California. The virus was detected in all 58 counties.
Source: California Department of Health