Epidemiology & Assessment

The Epidemiology and Assessment unit’s medical directors, public health nurses, and epidemiologists investigate individual cases and outbreaks of reported communicable disease (see List of Reportable Diseases) per the State of California Code of Regulations. We monitor disease trends, and often provide current statistics and other information to doctors, hospitals, the public and news media. For more information or CD reporting 24/7 call 714-834-8180.

For questions or comments, please email epi@ochca.com.

Latest News & Health Advisories

Eye on Influenza 2017-18 Issue 1November 9, 2017
Orange County has reported its first influenza-associated death of the season in a person less than 65 years of age. The decedent was a previously healthy toddler who was not vaccinated this season. All persons 6 months of age and older are recommended to get influenza vaccine annually. Influenza vaccine is readily available at numerous locations throughout the county; see www.ochealthinfo.com/phs/about/family/flu for more information.
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Hepatitis A Outbreaks in Homeless and Illicit Drug User Populations in CaliforniaNovember 8, 2017
San Diego, Santa Cruz, and Los Angeles Counties are experiencing Hepatitis A outbreaks primarily in their homeless and illicit drug user populations. San Diego County currently has 544 cases of Hepatitis A, including 20 deaths, Santa Cruz County has reported 76, and Los Angeles County has reported 15 cases.

For more information on the multi-jurisdiction outbreak:
https://www.cdph.ca.gov/Programs/CID/DCDC/Pages/Immunization/Hepatitis-A-Outbreak.aspx
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Provider Advisory: Update: Legionnaires' Disease Increase in the Anaheim areaNovember 8, 2017
The Orange County Health Care Agency has been notified of 11 individuals diagnosed with Legionnaires’ disease who live in or have visited the Anaheim area during the month of September. Eight have a history of visiting Disneyland Parks prior to developing illness; three have no history of Disneyland exposure. Case ages range from 52-94. Ten of the 11 ill were hospitalized, and one person died. OCHCA is currently investigating these cases, but have not yet identified a common exposure for all cases.
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Legionnaire’s Disease Increase in the Anaheim areaOctober 27, 2017
HCA has recently been notified of 8 individuals diagnosed with Legionnaire’s disease who live in or have visited the Anaheim area during the month of September: 2 are Anaheim residents, 5 were visitors who stayed in Anaheim between 9/12 and 9/27, and one is employed in Anaheim but lives in another county. We are currently investigating the cases, but have not yet identified any common exposure for all cases.
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Update: Hepatitis A Outbreaks in Homeless and Illicit Drug Using Populations in CaliforniaOctober 26, 2017
Outbreaks of Hepatitis A virus (HAV) infection have been identified in homeless and illicit drug using populations in multiple California counties. San Diego County has identified 516 cases of HAV infection, including 19 deaths, Santa Cruz County has had 73 cases, and Los Angeles County has had 14 cases. This week, the California Department of Public Health (CDPH) declared a statewide hepatitis A state of emergency. CDPH is advising that HAV vaccine be prioritized to communities that are experiencing active local spread of HAV.
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