Epidemiology & Assessment

Official start of the influenza season is less than two weeks awaySeptember 25, 2015
Flu activity is low across the U.S. now, but usually begins to increase in October. Providers are encouraged to begin vaccination efforts as soon as vaccine is available.

Human Cases of West Nile Virus (WNV) continue to be reported in Orange CountySeptember 25, 2015
Orange County has reported its first WNV-associated fatality this season, a resident of Buena Park in their 80’s with underlying medical conditions. So far this year, 26 human cases of WNV have been reported in Orange County, and California has a total of 201 human cases, including 10 WNV-related fatalities.

West Nile Virus (WNV) Activity is Increasing in Orange County

September 4, 2015
West Nile Virus season usually runs from April to November, with peak activity occurring in August and September. As of September 2, California has a total of 83 human WNV cases, including 2 WNV-related fatalities. 26 of these cases were reported in the previous week. This compares to 125 WNV cases statewide at this time last year. 415 cases from 38 states and the District of Columbia, including 10 fatalities, have been reported nationally so far this season (as of Sept.1).



Certain communicable diseases are required to be reported to the local health department (see List of Reportable Diseases) as per the State of California Code of Regulations. Epidemiology and Assessment (E&A) unit's medical directors, public health nurses, and epidemiologists investigate individual cases and outbreaks of reported communicable diseases. We monitor disease trends, and often provide current statistics and other information to doctors, hospitals, the public and news media. We may also provide education or preventive treatment in some circumstances. Although other units handle reports of HIV/AIDS, tuberculosis (TB) or sexually transmitted diseases (STDs), we do monitor their trends in Orange County. For more information or to report a Public Health emergency 24/7 call 714-834-8180.

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