JACKSON, MI -- The Michigan Department of Community Health confirmed Friday that norovirus caused some Michigan Tough Mudder participants to become ill after participating in the event June 29-30 at Michigan International Speedway in Brooklyn.

The confirmation follows more than 200 reports of illness. MDCH was notified by the Lenawee County Department of Health this week after Tough Mudder participants and spectators reported their symptoms. Some participants became sick soon after the event while others began showing symptoms several days later.

Not all who attended the event became ill, but those who were infected with norovirus reported nausea, vomiting, diarrhea and abdominal cramps.

MDCH encourages those concerned they may be infected to visit their doctor and drink a lot of water to prevent dehydration. The virus typically runs its course in one or two days, the report said.

Norovirus is transmitted through touching surfaces that have been contaminated or ingesting the virus through contaminated foods. It is unknown exactly what caused the contamination at Tough Mudder.