Three local children are believed to have been exposed to Shigatoxin-producing E. coli at the Northwestern Michigan Fair.

Grand Traverse County Health Department officials said the onset of symptoms, including bloody diarrhea, happened between Aug. 15 and 17, about two to four days after the fair wrapped south of Chum’s Corners in Blair Township. All three children attended the fair.

Dr. Michael Collins, medical director, said it seems likely the children contracted their infections from animals at the fair, though it likely will never be known exactly which animal or animals were sources.