Following investigations by local, state and federal public health authorities, the Centers for Disease Control and Prevention (CDC) has pinpointed romaine lettuce as the most-likely source of the outbreak.
Since the beginning of this month, 60 cases of E.coli O157:H7 have been reported across 10 states – with 37 in Missouri alone.
The outbreak, which according to the CDC appears to be over, has been attributed to a single batch of romaine lettuce produced at one farm un-named farm referred to as Farm A.
It is believed that the contamination involved only lettuce consumed between 5 and 24 October, as no positive test results have been taken from the farm.
Trace back investigations identified nine Schnucks grocery store locations, which are known only as Chain A in CDC documents, where more than one person reported buying a salad from the salad bar before becoming ill.
Contamination likely before store
“Collaborative investigative efforts of state, local, and federal public health agencies indicate that romaine lettuce sold primarily at several locations of a single grocery store chain (Chain A) was the likely source of illnesses in this outbreak,” a CDC report on the outbreak said.
“Contamination likely occurred before the product reached grocery store Chain A locations.”
“Romaine lettuce served on salad bars at all locations of grocery store Chain A had come from a single lettuce processing facility via a single distributor. This indicates that contamination of romaine lettuce likely occurred before the product reached grocery store Chain A locations.”
Inter-agency investigations have determined that a single batch of romaine lettuce harvested from an un-named farm (Farm A) was used to supply the identified Schnucks stores.
Initial findings at Farm A, which was no longer in production during the time of investigation, did not identify the source of the contamination.
Schnucks, which cooperated with the investigation, “voluntarily removed suspected food items from the salad bar on October 26, 2011, out of abundance of caution,” the CDC report added.
“Although no tests were positive for E.coli, the CDC believes romaine lettuce consumed between October 5 and 24 was the contaminant. The outbreak was traced back to a single lot of romaine lettuce harvested by a single farm,” said a statement released by Schnucks.
“Absent of any food safety violations or positive test results, the CDC declined to the name the grocer or the supplier.”
“However, leaders of Schnuck Market Inc are confirming that Schnucks is the entity referred to by the CDC as ‘grocery store chain A,’ but for the same reasons provided by the CDC, Schnucks declined to name the supplier,” Schnucks added.
A woman, who became infected with E.coli O157:H7 after eating romaine lettuce from a Schnucks store, has announced that she will sue the store.