In a follow-up on the hepatitis A outbreak in San Diego County, CA, the number of cases reported this year has climbed to 312, including 10 fatalities, according to latest health department data.

Of the cases, nearly seven out of 10 patients required hospitalization for their illness (215).

LISTEN: Talking Hepatitis A with Dr Amesh Adalja

The County of San Diego Health and Human Services Agency says the investigation into the outbreak is ongoing.

It has been challenging because of the long incubation period of the disease (15 to 50 days) and the difficulty experienced to contact many individuals sickened with the illness who are homeless and/or illicit drug users. To date, no common source of food, beverage, or other cause has been identified; as a result, the source of the outbreak remains undetermined.

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