As of June 28, 2016, 42 people infected with the outbreak strain of STEC O121 have been reported from 21 states – Alabama 1, Arkansas 1, Arizona 2, California 2 (up 1), Colorado 4, Iowa 1, Illinois, 4, Indiana 1 (New), Massachusetts 2, Maryland 1, Michigan 4, Minnesota 3, Missouri 1, Montana 2 (up 1), New York 1, Oklahoma 2, Pennsylvania 2, Texas 2, Virginia 2, Washington 3 (up 1), and Wisconsin 1.
Illnesses started on dates ranging from December 21, 2015 to June 8, 2016. Ill people range in age from 1 year to 95, with a median age of 18. Eighty-one percent of ill people are female. Eleven ill people have been hospitalized. No one has developed hemolytic uremic syndrome, a type of kidney failure, and no deaths have been reported.
In June 2016, laboratory testing by the U.S. Food and Drug Administration (FDA) isolated STEC O121 from samples of General Mills flour collected from the home of an ill person in Oklahoma. The STEC O121 isolated from the flour sample has the same PFGE pattern, or DNA fingerprint, as the outbreak strain. The flour collected in Oklahoma was not included in the initial General Mills recall.
In the same month, FDA identified STEC O121 in an open sample of General Mills flour collected from the homes of ill people in Colorado and Arizona. Whole genome sequencing (WGS) showed that the STEC O121 isolates from the flour samples were closely related genetically to the STEC O121 isolates from ill people. The flour sample that was tested came from lots of flour included in the initial recall announced by General Mills.
On July 1, 2016, General Mills expanded the recall to include some flours sold under the same brand names included in the initial recall: Gold Medal Flour, Gold Medal Wondra Flour, and Signature Kitchens Flour. CDC recommends that consumers, restaurants, and retailers do not use, serve, or sell the recalled flours.