A public health alert was issued by the Michigan Department of Community Health after authorities found out that 26 people were contaminated with E. coli O157:H7. All the contaminated people had eaten at restaurants or similar business or facilities and the source of the contamination was iceberg lettuce.

The iceberg lettuce is being sold in bagged, industrial-sized packages through wholesale venues. Most clients are restaurants and institutions. Authorities said there was no evidence that the iceberg lettuce sold at grocery stores was also contaminated.

Among the people who contaminated the disease, there were also seven Michigan State University students. E. coli has also contaminated 6 people in the state of Illinois, New York, and Ohio.

Authorities urged restaurants and similar businesses not to use the iceberg lettuce they already purchased and have in stock. The lettuce made by Aunt Mid’s Produce Co was linked to most infection cases.

A campaign of testing the products suspected of being infected is currently being carried out by the U.S. Centers for Disease Control and Prevention (CDC).

Authorities are currently carrying out a full investigation of the incident.

"Our top priority at the Michigan Department of Community Health is to protect the public," said Dr. Gregory Holzman, chief medical executive for Michigan Department of Community Health (MDCH).

"We appreciate all of the assistance from Aunt Mid's. They have been very helpful in this investigation. We want to ensure that the public's health and well-being is protected. Even though the investigation is ongoing, available evidence is strongly pointing to iceberg lettuce."

The list of people affected by E. coli through iceberg lettuce includes 5 inmates at the Lenawee County Jail, 3 students at the University of Michigan (Washtenaw County), 4 in Macomb County, 3 each in Wayne, 2 in Kent counties, and one each in St. Clair and Oakland counties, MDCH informed.

The E. coli O157:H7 usually causes stomach cramps, diarrhea, vomiting and in some cases fever. In some severe and rare cases the disease can lead to death.