June 19, 2019

CDC, several states, and the U.S. Department of Agriculture’s Food Safety and Inspection Service (USDA-FSIS ) investigated a multistate outbreak of Shiga toxin-producing E. coli O103 infections.

Public health investigators used the PulseNet system to identify illnesses that may have been part of this outbreak. PulseNet is the national subtyping network of public health and food regulatory agency laboratories coordinated by CDC. DNA fingerprinting is performed on E. coli bacteria isolated from ill people by using techniques called pulsed-field gel electrophoresis (PFGE) and whole genome sequencing (WGS). CDC PulseNet manages a national database of these DNA fingerprints to identify possible outbreaks. WGS gives a more detailed DNA fingerprint than PFGE. WGS performed on E. coli from ill people in this outbreak showed that they were closely related genetically. This means that the ill people were more likely to share a common source of infection.

A total of 209 people infected with the outbreak strain of E. coli O103 were reported from 10 states. A list of the states and the number of confirmed cases in each can be found on the Map of Reported Cases page.

Illnesses started on dates from March 1, 2019, to May 1, 2019. Ill people ranged in age from less than 1 year to 84 years, with a median age of 18. Fifty-one percent were female. Of 191 people with information available, 29 (15%) were hospitalized. Two cases of hemolytic uremic syndrome were reported. No deaths were reported.

WGS analysis was performed on 187 isolates from ill people and 10 isolates from food samples. WGS analysis of 184 isolates from people and 10 from food did not predict any antibiotic resistance; 3 patient isolates had predicted resistance to ampicillin, sulfisoxazole, tetracycline, or trimethoprim-sulfamethoxazole. Standard antibiotic resistance testing by CDC’s National Antimicrobial Resistance Monitoring System (NARMS) of two patient isolates also did not show resistance. These resistance findings do not affect treatment guidance since antibiotics are not recommended for patients with Shiga toxin-producing E. coli infections.

Investigation of the Outbreak

This multistate investigation began on March 28, 2019, when officials in Kentucky and Georgia notified CDC of this outbreak. Epidemiologic and laboratory evidence indicated that ground beef was the 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. Of the 159 people interviewed, 125 (79%) reported eating ground beef. This percentage is significantly higher than results from a survey pdf icon[PDF – 787 KB] of healthy people. Ill people bought or ate ground beef from several different grocery stores and restaurants. Many ill people bought large trays or chubs of ground beef from grocery stores and used the meat to make dishes like spaghetti and sloppy joe.

Officials at USDA-FSIS, in Kentucky, and in Tennessee collected ground beef from a restaurant and an institution where ill people reported eating. Laboratory testing identified the outbreak strain of E. coli O103 in the ground beef collected in Tennessee. A different strain of E. coli O103 was identified in the ground beef collected in Kentucky. This strain was not linked to illnesses.

Two companies recalled raw ground beef products because they may be contaminated with E. coli. Grant Park Packing in Franklin Park, Ill., recalledexternal icon approximately 53,200 pounds of raw ground beef products on April 24, 2019. K2D Foods, doing business as Colorado Premium Foods, in Carrollton, Ga., recalledexternal icon approximately 113,424 pounds of raw ground beef products on April 23, 2019. These products were sold to restaurants and institutions.

USDA-FSIS and state regulatory officials collected products for testing at retailers and establishments, and all products tested were negative for E. coli. USDA-FSIS conducted traceback investigations to determine the source of ground beef supplied to grocery stores and restaurants where ill people ate. Ill people in this outbreak ate ground beef from many sources. No single supplier, distributor, or brand of ground beef was identified. Consumers should handle ground beef safely and cook it thoroughly.

As of June 19, 2019, this outbreak appears to be over.