West Nile virus (WNV) cases in Orange and Los Angeles counties accounted from 60 of the 74 new cases of the mosquito borne virus reported on California during the past week, according to the California Department of Public Health (CDPH) today.

Culex mosquito
Culex quinquefasciatus
Image/CDC

With the additional 74 human WNV cases this past week, this brings California’s total to 562 cases from 29 counties, far more than any other state this year. In fact, Orange County’s 201 WNV cases is more than any individual state as of Oct.7.

The new cases were reported from the following counties: Butte (1), Contra Costa (1), Fresno (3), Los Angeles (31), Orange (29), Riverside (1), San Diego (2), San Joaquin (1), Santa Clara (1), Tehama (1), and Tulare (3). In addition, California reported an additional WNV death, bringing that total to 17.

The 562 cases reported year-to-date is more than double the 2013 total at this time of 272.

In 2013, California reported a total of 379 cases during the entire year and 479 in 2012. The worst year on record for California was 2005 when the state recorded 880 cases.

Since it’s first case seen in 2002 to 2013, California reported 4,005 cases in total.

As of October 7, a total of 46 states and the District of Columbia have reported West Nile virus infections in people, birds, or mosquitoes. Overall, 1,301 cases of West Nile virus disease in people and 47 deaths have been reported to CDC.

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