With Halloween only hours away, two new E. coli outbreaks have shown up to haunt the nation’s Romaine growers because genetic links to the past have been discovered.
The two outbreaks of Shiga toxin-producing E. coli O157: H7 (STEC) illnesses are under investigation by the Food and Drug Administration (FDA), Centers for Disease Control, and Prevention (CDC), along with various state and local health departments.
“We do not know what food is causing people to get sick or whether it involves an FDA-regulated food product,” said Frank Yiannas, FDA Deputy Commissioner for Food Policy and Response. “However, we have seen similar recurring, emerging, or persistent strains of E. coli in recent outbreaks. E. coli O157: H7 can contaminate many foods, and we cannot assume that the current outbreaks are linked to historically associated foods like romaine and other leafy greens. There is no information currently to indicate that people should avoid any specific food.”
“We are issuing this update early in our investigation as part of our continued commitment to transparency and early communication, ” he added. “We are also working toward making a new resource available soon on our website to provide early updates on new and active investigations. We are closely working with our partners at the CDC and the states to pinpoint the sources of the E. coli O157: H7 illness outbreaks and will share information as it becomes available.”
- Two distinct outbreaks of foodborne illness of E. coli O157: H7 (STEC) are under investigation involving recurring, emerging, or persistent strains.
- To support the CDC’s epidemiological investigation, the FDA is conducting traceback investigations, on-site inspections, and sampling in an effort to rule in or rule out suspect foods.
- While there have been no specific foods definitively linked to these outbreaks, the FDA has taken a number of actions to prevent foodborne illness outbreaks and strengthen safeguards for consumers as part of our New Era of Smarter Food Safety initiative, including the issuance of the Leafy Greens STEC Action Plan, which outlined actions that the FDA plans to take in 2020 to advance work in three areas: prevention, response and addressing knowledge gaps. Actions completed this year include:
- Publication of a report following our investigation into three 2019 outbreaks of E. coli O157: H7 in leafy greens grown in the Salinas Valley, California, which further increased our understanding of how leafy greens may have become contaminated and the impact of animal activity on adjacent and nearby land.
- In collaboration with the California Department of Food and Agriculture (CDFA), prioritized inspections and other surveillance activities at farms identified by traceback in the 2019 outbreaks during the 2020 growing/harvest season specifically to further investigate harvest operations and factors in the environment that may have contributed to the introduction and transmission of E. coli O157: H7 that led to the contamination of romaine lettuce in the Salinas Valley growing area.
- Initiated a longitudinal research study with CDFA and other agricultural partners in California to improve food safety through our enhanced understanding of the ecology of human pathogens in the environment that may cause foodborne illness outbreaks. In addition, our inspection activity in the Central Coast, Central Valley, and Imperial Valley in California and in Yuma, Arizona, includes sampling and testing for pathogenic E. coli and Salmonella with a new sampling assignment as well as sampling assignments for the last few years.
Outbreak 1 – possibly linked to the 2018 Yuma Romaine E. coli Outbreak.
As of October 28, 2020, a total of 21 people infected with the outbreak strain of E. coli O157: H7 have been reported from eight states.
Illnesses started on dates ranging from June 6, 2020, to October 5, 2020. Ill people range in age from 2 to 75 years, with a median age of 24 years. Sixty-seven percent of ill people are female. Of 16 ill people with information available, 8 hospitalizations have been reported, including 1 person who developed hemolytic uremic syndrome (HUS), a type of kidney failure. One death has been reported from Michigan.
Several ill people have been identified as part of an illness cluster at a restaurant. An illness cluster is defined as two or more people from different households who report eating at the same restaurant location, attending a common event, or purchasing food at the same grocery store in the week before becoming ill. Investigating illness clusters can provide critical clues about the source of an outbreak. If several unrelated ill people ate or shopped at the same location of a restaurant or store within several days of each other, it suggests that the contaminated food item was served or sold there.
The strain of E. coli O157: H7 causing illness in this outbreak has previously caused outbreaks linked to different sources, including an outbreak linked to romaine lettuce in 2018. However, food linked to a previous outbreak alone is not enough to prove a link in another outbreak of the same strain. This is because different foods can be contaminated by the same strain of bacteria.
Outbreak 2 – possibly linked to 2019 Salinas Romaine E. coli Outbreak.
As of October 28, 2020, a total of 23 people infected with the outbreak strain of E. coli O157: H7 have been reported from 12 states.
Illnesses started on dates ranging from August 17, 2020, to October 8, 2020. Ill people range in age from 5 to 81 years, with a median age of 21 years. Sixty-seven percent of ill people are female. Of 15 ill people with information available, 10 hospitalizations have been reported, including 2 people who developed hemolytic uremic syndrome (HUS), a type of kidney failure. No deaths have been reported.
State and local public health officials are interviewing ill people to determine what they ate and other exposures in the week before they got sick. People have reported eating a variety of foods, including leafy greens. Of the 13 people interviewed to date, all reported eating various types of leafy greens, like iceberg lettuce (9), romaine lettuce (8), mixed bag lettuce (6), and spinach (9).
This outbreak is caused by the same strain of E. coli O157: H7 that caused an outbreak linked to romaine lettuce in 2019. However, food linked to a previous outbreak alone is not enough to prove a link in another outbreak of the same strain. This is because different foods can be contaminated by the same strain of bacteria.
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