Staffers from the federal Centers for Disease Control and Prevention are stationed in Flint to help state and local health officials investigate an outbreak of shigellosis, a highly contagious gastrointestinal illness.
The Genesee County Health Department says Wednesday that 177 cases have been reported in Genesee and Saginaw counties since March 1, 2016.
Shigella outbreaks are not unusual. The illness is a bacterial infection spread through just a tiny amount of infected fecal matter. Diarrhea, fever, vomiting and stomach cramps may occur.
Hand-washing is encouraged as a way to stop the bacteria's spread.
A source of the outbreak has not been identified, though the number of cases has slowed since September.
The CDC was called in at the request of health officials from both counties and the state.