Epidemiology & Assessment

Orange County Reports First West Nile Virus Positive Mosquito Samples and Dead Birds This SeasonMay 23, 2016
These are the first indications of WNV in Orange County this year. See the Orange County Mosquito and Vector Control District (OCMVCD) website, www.ocvcd.org, for more information about mosquito and bird testing. No human cases have been reported yet this season in California. The first human cases in Orange County are typically reported in June or July. Now is a great time to remind patients, families, friends and neighbors to remove sources of standing water from around their homes and make sure their windows and screens are in good repair to decrease their risk of WNV infection.

Third Mumps Case Identified in College Student from Orange CountyApril 14, 2016
An Orange County college student was diagnosed with mumps last week, the third Orange County student diagnosed with mumps in the last two months. All three attend college outside of Orange County, but all three were in the County when they became ill and were diagnosed. Outbreaks of mumps have occurred at college campuses around the country since late 2015. As students travel to and from school during spring break, community exposure to mumps cases may occur.

Zika Virus Infection: Current Recommendations for Orange County Medical ProvidersMarch 10, 2016
Health care providers who have clinical questions, wish to arrange testing for a patient, or have a suspect case to report, should call the Epidemiology and Assessment Program at 714-834-8180.


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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