Public health officials and the Michigan Department of Health and Human Services (MDHHS) are continuing to see an elevated number of hepatitis A cases in the state.

Since the beginning of the outbreak in August 2016, public health response has included increased healthcare awareness efforts, public notification and education, and outreach with vaccination clinics for high-risk populations. No common sources of food, beverages, or drugs have been identified as a potential source of infection. Transmission appears to be through direct person-to-person spread and illicit drug use. Those with history of injection and non-injection drug use, homelessness or transient housing, and incarceration are thought to be at greater risk in this outbreak setting. Notably, this outbreak has had a high hospitalization rate.

Michigan Hepatitis A Outbreak Cases and Deaths as of April 4, 2018

Cases Hospitalizations Deaths
802 644 (80.4%) 25 (3.1%)


 Confirmed Cases Referred August 1, 2016-April 4, 2018 
Meeting the MI Hepatitis A Outbreak Case Definition
 County (or city) Total Cases  County (or city) Total Cases
 Macomb 216  Sanilac 6
 City of Detroit 167  Lapeer 6
 Wayne 138  Livingston 6
 Oakland 108  Grand Traverse 4
 St. Clair 30  Allegan 1
 Ingham 24  Clare 1
 Washtenaw 17  Hillsdale 1
 Monroe 17  Huron 1
 Genesee 13  Ionia 1
 Isabella 8  Kent 1
 Calhoun 7  Leelanau 1
 Shiawassee 7  Lenawee 1
 Eaton 5  Newaygo 1
 Clinton 3  Schoolcraft 1
 Gratiot 3  Van Buren 1
 Saginaw 3  Other* 1
 Mecosta 2

 *Jackson Michigan Department of Corrections