State and county public health officials in Michigan are investigating five confirmed Shiga-toxin producing E. coli O157 illnesses, with preliminary information pointing to undercooked ground beef as the likely source. The illnesses have been reported in five adults between 20-41 years old who noticed symptoms from April 22 to May 1. Three people have been hospitalized, according to the Michigan Department of Community Health. Officials said that none of the ill individuals have developed hemolytic uremic syndrome, a severe complication of E. coli O157 infection, and that no deaths have been reported. So far, the investigation indicates that the sickened individuals ate undercooked ground beef at several different restaurants in multiple locations. The Michigan Department of Agriculture and Rural Development is working with local health departments and the U.S. Department of Agriculture to determine where the ground beef came from and where it was distributed. “E. coli O157 illnesses can be very serious or life-threatening, especially for young children, older adults, and people who are immunocompromised,” said Dr. Matthew Davis, the health department’s chief medical executive. “Whether you cook at home or order in a restaurant, ground meats, including ground beef, should always be cooked thoroughly to the proper temperature.” Consumers are advised to safely prepare their raw meat products, including fresh and frozen, and only eat ground beef that has been cooked to an internal temperature of 160 degrees F. Use a food thermometer to be sure that ground beef has been cooked to a temperature high enough to kill harmful bacteria. A gastrointestinal infection caused by Shiga toxin-producing E. coli O157 can cause diarrhea (often bloody) and abdominal cramps three to four days after exposure (incubation ranges from two to 10 days). Most people get better within five to seven days, but the elderly, infants, and those with weak immune systems are more likely to develop severe or even life-threatening illness such as hemolytic uremic syndrome. Persons who are ill with these symptoms and have consumed ground beef recently should consult with their medical provider and ask about being tested for an E. coli infection.