The number of potential customers that were affected by a food borne illness outbreak at a Chipotle Mexican Grill in Ohio may be much higher than initially believed.

The Delaware General Health District said Wednesday that it had received a total of 518 inquiries — 95 emails and 423 calls — related to a possible outbreak stemming from a Chipotle in Powell, Ohio.

So far, staff at the local health department has been able to interview more than 200 people who self-reported nausea, diarrhea and fever, among other symptoms, after eating at the restaurant. In addition fecal and food samples have been delivered to the Ohio Department of Health for laboratory testing.

The health department said it will be testing for salmonella, shigella, E. coli, and norovirus in both samples. The food samples will also be tested for bacillus cereus and clostridium perfringens, two bacteria that can cause the symptoms that have been reported.

Laurie Schalow, a spokeswoman for Chipotle, declined to comment.