ST PAUL, Minn. — Minnesota health officials say there's an outbreak in parts of the state of hepatitis A, a virus that can cause severe liver damage.

Minnesota Health Department (MDH) Infectious Disease Director Kris Ehresmann said the outbreak includes 23 cases in nine counties: Pine (5), Hennepin (3), Kanabec (3), Mille Lacs (3), St. Louis (3), Washington (3), Chisago (1), Dakota (1) and Kandiyohi (1). Patients in 13 of those cases have been hospitalized, and all have been discharged. 

The virus most commonly spreads when people eat, drink or place an object in their mouth that's contaminated with fecal matter from someone who has the virus.

"Since 2016 there's been an outbreak across multiple states of hepatitis A and it has been focused in three risk groups," Ehresmann said. 

High-risk groups include people who use street drugs (injection or non-injection), those experiencing homelessness or unstable housing, and people who are or have recently been incarcerated.

While anyone who is not vaccinated can get hepatitis A, those who are homeless or who use street drugs are at higher risk, particularly if they don’t have access to sanitation, restroom facilities and handwashing facilities. 

MDH has seen an increase in cases in the state since May. While initial cases were clustered in east-central Minnesota and had links to each other, more recent cases occurred in counties in other parts of the state. The infection source is not known for some cases, suggesting some community transmission among those in high-risk groups.

The Minnesota Department of Health is pushing for more widespread vaccination efforts in high-risk areas such as jails and homeless shelters.

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“We have been working with our public health partners to respond to individual cases and prevent future cases,” Ehresmann said. “Declaring an outbreak is a significant step because it allows us to access additional resources to fight the outbreak.”

The hepatitis A vaccination has been recommended for kids since 2006, but many adults have not been vaccinated for it. 

"Our recommendation for hepatitis A vaccine is really anybody who eats probably should consider the vaccine," Ehresmann said.

In the last three years, there have been more than 23,600 cases of hepatitis nationally, with 233 deaths.