Update – Outbreak of E. coli Infections Linked to Romaine Lettuce

CDC, public health and regulatory officials in several states, Canada, and the FDA are investigating a multistate outbreak of Shiga toxin-producing Escherichia coli O157:H7 (E. coli O157:H7) infections. Read food safety alert.

As of December 6, 2018, 52 people infected with the outbreak strain of E. coli O157:H7 have been reported from 15 states. A list of the states and the number of cases in each can be found on the Map of Reported Cases page.

Illnesses started on dates ranging from October 5, 2018 to November 18, 2018. Ill people range in age from 1 to 84 years, with a median age of 30. Sixty-nine percent of ill people are female. Of 45 people with information available, 19 (42%) have been hospitalized, including two people who developed hemolytic uremic syndrome, a type of kidney failure. No deaths have been reported.

Illnesses that occurred after November 14, 2018, might not yet be reported due to the time it takes between when a person becomes ill with E. coliinfection and when the illness is reported. This takes an average of two to three weeks.

Investigation of the Outbreak

Epidemiologic and traceback evidence indicates that romaine lettuce from the Central Coastal growing regions of northern and central California is a likely source of this outbreak.

In interviews, ill people answered questions about the foods they ate and other exposures in the week before they became ill. Twenty-four (83%) of 29 people interviewed reported eating romaine lettuce. This percentage is significantly higher than results from a survey[PDF – 787 KB] of healthy people in which 47% reported eating romaine lettuce in the week before they were interviewed. Ill people reported eating different types of romaine lettuce in several restaurants and at home.

Preliminary traceback information from the FDA indicates that ill people in this outbreak ate romaine lettuce harvested from the Central Coastal growing regions of northern and central California. The specific California counties FDA identified in the traceback investigation are Monterey, San Benito, San Luis Obispo, Santa Barbara, Santa Cruz, and Ventura. At this time, no common grower, supplier, distributor, or brand of romaine lettuce has been identified.

The FDA, along with CDC and state partners, is investigating farms and cooling facilities in California that were identified in traceback. CDC collected samples of water to test for E. coli O157:H7; these test results are pending.

This investigation is ongoing, and CDC will provide more information as it becomes available.