The Minnesota Department of Health has confirmed that at least 22 people on the Fond du Lac Band of Lake Superior Chippewa Reservation near Duluth have recently been sickened by foodborne illness linked to E. coli bacteria. The first illness was reported July 17.

The investigation is ongoing, but no specific cause has yet been found. The outbreak strain is believed to be E. coli O157, according to a department spokesman, which is not the one recently linked to Applebee’s restaurants in Minnesota.

The sickened reservation residents are being called and interviewed by a state epidemiologist, an environmental health supervisor and University of Minnesota graduate epidemiology students, the spokesman said.

Recent events on the reservation, including powwows, picnics, weddings, potlucks and outdoors meetings, have likely contributed to opportunities for foodborne illness. Residents were encouraged to throw away any leftover foods from these events.

Those experiencing symptoms of foodborne illness are advised to contact a health care provider or the local emergency room. More information and specific symptoms related to E. coli infection is available here.

The Minnesota Department of Health has provided the following contact numbers: toll free is 1-877-FOOD ILL (1-877-366-3455) or 1-651-201-5277 for individuals who have questions or would like to learn more about E. coli or any other foodborne illness. They advise callers to leave a message and someone will call back promptly.