The Los Angeles Times reported yesterday that West Nile virus is off to an early start in 2007 with cases of infected mosquitoes, horses or birds having been found in 26 of California's 58 counties. The newspaper said three Kern County residents are the only known human cases. However, a day later, a story in the Sacramento Bee reported a human case of West Nile infection in Stanislaus County.
The state could be on its way to beating the record for the disease set last year. In 2006, California recorded 276 human West Nile virus infections and seven deaths, according to a news release by Kathy Keatley Garvey of the UC Davis Mosquito Research Program. Fifty-four counties had West Nile virus activity. Fifty-eight horses tested positive for West Nile virus last year, and 24 died or were euthanized.
West Nile virus is transmitted to humans and animals by infected mosquitoes. First isolated in 1937 in the West Nile District of Uganda, the virus spread to New York in 1999 and reached California in 2002.
According to an informative Q&A by the Centers for Disease Control, the experience of West Nile virus infection in humans ranges from no symptoms at all to a severe illness that requires hospitalization and can lead to death. Symptoms of West Nile fever mimic the flu, with headache, fatigue, body aches and sometimes a skin rash.
A number of research projects aimed at better understanding and controlling West Nile virus will be presented at the annual UC Davis Mosquito Research Program Grant Proposal Presentation Day July 19 at UC Riverside. For more information see the program's news release, posted July 11 on the UC ANR news site.
