UPPER SANDUSKY, Ohio -- Health officals are trying to determine whether a cluster of E. coli cases can be linked to the Wyandot County Fair.

At least 20 people have reported symptoms of the infection, including diarrhea, severe abdominal cramps or bloody diarrhea.

All of them attended the fair. Health officials are awaiting test results from those infected. Seven cases of E. coli have been confirmed.

Investigators say that they'll interview healthy fairgoers to determine differences in food, water and activities.

Most people recover from E. coli infection in five to 10 days, but some develop life-threatening complications such as kidney failure.

The fair was from Sept. 11-16. Wyandot County is just north of Marion.

For more information on E. coli, click here.