CALIFORNIA, United States (AFP ) — A record outbreak of Hepatitis A has killed 14 people and put scores in hospital in San Diego, hitting mostly homeless and patients using intravenous drugs.

The latest data from San Diego County in California show that more than 350 cases have been diagnosed since the beginning of the year. Most of those have taken been identified since July, and 264 people have needed care in hospital.

“As hepatitis A goes, the number of deaths is greater than in other large outbreaks reported to CDC, though not all outbreaks are reported to CDC,” a spokeswoman for the Centers for Disease Control and Prevention told AFP.

Another outbreak in 2003 linked to green onions in Pennsylvania caused three deaths and sent 124 people to hospital.

Authorities have not yet identified the cause of the latest outbreak.

But they say it is being spread person-to-person and through contact with a fecally contaminated environment.

This puts homeless people especially at risk since they do not have regular access to sanitary facilities and clean water to wash their hands, state health authorities noted.