Hepatitis A Outbreaks

Hepatitis A Outbreaks Since 2013

Highlights

Fluctuations in the reported cases have occurred in the last 20 years due to large outbreaks. After a long downward trend, the first increase between 2012 and 2013 (1,562 and 1,781 reported cases, respectively) was due to a large multistate outbreak associated with pomegranate arils imported from Turkey.

Between 2015 and 2016, the reported cases again increased from 1,390 in 2015 to 2,007 cases in 2016. The 2016 increase was due primarily to two foodborne hepatitis A outbreaks, each of which was linked to contaminated imported foods.

Substantial increases in incident cases of hepatitis A occurred from late 2016 through 2019 due to outbreaks reported to CDC among people who use drugs and people experiencing homelessness. After these increases, from 2019 to 2023, the rate of newly reported hepatitis A cases decreased 91%. The number of cases in 2023 (1,648) was 1.2 times as high as in 2015 (1,390) before the outbreaks caused by person-to-person transmission were first reported. In 2022 and 2023 there were multistate outbreaks linked to imported organic strawberries. In 2026, there was a multistate outbreak potentially linked to imported frozen clams that is over.

Disruptions to health care access and health department surveillance capacity during the COVID-19 pandemic may have affected the ability to detect and report all hepatitis A cases in 2020 and 2021.