Epidemiology & Assessment

EbolaMarch 31, 2015

The 2014 Ebola outbreak has been the largest recorded in history, and continues to affect the West African countries of Sierra Leone, Liberia, and Guinea. The Orange County Health Care Agency has been working with community partners to assure our county is prepared. For more information, see http://ochealthinfo.com/phs/about/dcepi/epi/disease/ebola


Dengue and Chikungunya in Mexico and Latin America

March 27, 2015

Regions of Mexico and Latin America have experienced a recent increase in chikungunya and continued dengue
infections. Travelers visiting affected areas should take appropriate precautions for avoiding mosquito bites during the day and at night.


Measles in Orange County

March 27, 2015

Orange County experienced a significant measles outbreak in December, 2014 through February, 2015. 35 measles cases were identified in our County in an outbreak that started at Disneyland theme park in mid-December 2014. The outbreak has led to over 140 infections in at least seven states.



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.

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