A new measles outbreak has been confirmed in Central Michigan, part of a trend up in cases during the past few months. 

An outbreak involves three or more related cases of measles. This is an extremely contagious disease that was considered eliminated in the U.S. after decades of vaccination efforts. 

The latest outbreak is in Osceola County, after the Central Michigan District Health Department confirmed on Thursday that there are additional cases traced to local residents who were infected while traveling out of state in June. The first known case of this outbreak was confirmed on July 18. The health district serves Arenac, Claire, Isabella, Osceola and Roscommon counties. 

The Michigan Department of Health and Human Services has been tracking the 2025 outbreaks, with seven cases now in Osceola County, four in Grand Traverse County, and four in Montcalm County. With additional scattered cases across the state, Michigan has seen a total of 27 confirmed measles cases so far this year. 

Measles symptoms show up about 7 to 14 days after exposure to the virus, according to the Centers for Disease Control. They include high fever, cough and a rash. Serious complications can result, especially among children aged 4 and younger.