CDC seeking source for new E. coli outbreak

CDC, public health and regulatory officials in several states, the U.S. Food and Drug Administration (FDA), and the U.S. Department of Agriculture’s Food Safety and Inspection Service (USDA-FSIS) are collecting different types of data to identify the food source of a multi-state outbreak of E. coli O157:H7 infections.

Epidemiologic data

As of Feb. 1, 2021, a total of 16 people infected with the outbreak strain have been reported from five states. This map shows where sick people live.

Illnesses started on dates ranging from Dec. 23, 2020, to Jan. 7, 2021. This chart shows when people got sick. Recent illnesses may not yet be reported as it usually takes two to four weeks to link illnesses to an outbreak.

Sick people range in age from 10 to 95 years, with a median age of 31, and 88% are female. Of 12 people with information available, nine have been hospitalized. Of 11 people with information, three developed a type of kidney failure called hemolytic uremic syndrome (HUS). One death has been reported from Washington.

State and local public health officials are interviewing people to find out what foods they ate in the week before they got sick.

Laboratory and traceback data

Public health investigators are using the PulseNet system to identify illnesses that may be part of this outbreak. CDC PulseNet manages a national database of DNA fingerprints of bacteria that cause foodborne illnesses. DNA fingerprinting is performed on bacteria using a method called whole genome sequencing (WGS).

WGS showed that bacteria from sick people’s samples are closely related genetically. This means that people in this outbreak likely got sick from eating the same food.

WGS also showed that this outbreak strain has been previously linked to various sources, including romaine lettuce, ground beef and recreational water. More information is needed to identify the source of this outbreak.