Epidemiology & Assessment

Chikungunya in the AmericasJuly 21, 2014
On July 17, 2014 the Florida Department of Health confirmed the first two cases of locally acquired chikunguna fever in the United States. For more information, click here.

Orange County Reports First Human West Nile Virus Case of 2014July 10, 2014
A Santa Ana man has tested positive for West Nile Virus (WNV) infection, becoming the County’s first human WNV infection in 2014. This is the 10th human case of WNV reported in California. The man was admitted to the hospital in late June with symptoms of West Nile Virus, and is now at home recovering.

California’s First Human West Nile Virus Infections for This Season IdentifiedJune 19, 2014
On June 19, the California Department of Public Health reported this season’s first two human infections with West Nile Virus (WNV) in the state, one each in Contra Costa and San Joaquin Counties.
Many counties in the state have reported WNV-positive bird and/or mosquito testing. No human cases have been identified in Orange County this season. But the virus is present in our community, as multiple birds and mosquito pools have tested positive. For more information on WNV epidemiology, click here
For additional information, see www.cdc.gov/westnile/index.html.


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.

Epidemiology Page Index

Additional Topics

Orange County links

More Disease Information