TUCSON, Ariz. (AP) - Health officials in southern Arizona are reporting an increase in hepatitis A cases in Pima County, prompting a partnership among local health agencies to boost vaccinations and awareness.

There have been 22 confirmed cases in Pima County so far this year. Officials say that represents a sharp increase from just five cases in 2017 and 12 cases in 2016.

Pima County Health Department Director Marcy Flanagan says that around the U.S., outbreaks are becoming more common and can be very difficult to stop once they begin.

The spike in cases has been linked to people experiencing homelessness and people who use illicit drugs.

Hepatitis A is highly contagious and can range from a mild illness lasting a few weeks to a severe one persisting for months. Although rare, it can cause liver failure and even death.

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