- This outbreak appears to be over as of June 28, 2018.
- CDC, public health and regulatory officials in several states, and the U.S. Food and Drug Administration (FDA) investigated a multistate outbreak of E. coli O157:H7 infections.
- 210 people infected with the outbreak strain were reported from 36 states.
- 96 people were hospitalized, including 27 people who developed a type of kidney failure called hemolytic uremic syndrome.
- 5 deaths were reported from Arkansas, California, Minnesota (2), and New York.
- Epidemiologic, laboratory, and traceback evidence indicated that romaine lettuce from the Yuma growing region was the likely source of this outbreak.
- CDC laboratory testing identified the outbreak strain of E. coli O157:H7 in canal water samples taken from the Yuma growing region. FDA is continuing to investigate the outbreak to learn more about how the E. coli bacteria could have entered the water and ways this water could have contaminated romaine lettuce.
- According to the FDA, the last shipments of romaine lettuce from the Yuma growing region were harvested on April 16, 2018, and the harvest season has ended. Contaminated lettuce that made people sick in this outbreak should no longer be available.
- The Public Health Agency of Canada (PHAC) identified ill people in several Canadian provinces infected with the same DNA fingerprint of E. coli O157:H7. On June 22, 2018, PHAC reported that the outbreak in Canada appears to be over.
- Consumers should follow these steps to help keep fruits and vegetables safer to eat.
- Read more on general ways to prevent E. coli infection. Important steps to take are to cook meat thoroughly, and wash hands after using the restroom or changing diapers, before and after preparing or eating food, and after contact with animals.
What was the Problem and What was Done?
- On April 4, 2018 FDA learned about a cluster of E. coliO157:H7 infections in two states and on April 5, 2018 a new cluster was reported in multiple states. In the following weeks, the FDA, CDC, and state partners worked together to collect additional information and conduct traceback activities to identify a food item of interest.
- On April 10, 2018 the FDA publicly communicated about the outbreak, but was unable to identify a food source. The agency recommended that consumers practice safe food handling and preparation and to consult a health care provider if they think they might have symptoms of E. coli infection.
- Interviews with ill people allowed health partners to identify chopped romaine from the Yuma growing region as the likely source of contamination on April 13, 2018.
- April 16, 2018 was the final day of romaine harvesting in the Yuma growing region, however at the time chopped romaine had just been identified as the likely source allowing the traceback investigation to begin and at this point, no specific farms in the Yuma region had been identified. FDA did not receive confirmation of the final harvest date until May 2, 2018.
- On April 19, 2018, Alaska health partners announced that eight persons with E. coli O157:H7 infections from a correctional facility have been confirmed as part of the outbreak. These individuals ate whole-head romaine lettuce from the Yuma growing region. Following this announcement, the FDA advised consumers to avoid all romaine lettuce from the Yuma growing region. This region generally supplies romaine lettuce to the U.S. during November-March each year. In the following weeks FDA continued its traceback investigation, part of which was able to trace the Alaskan correctional facility back to a single farm, which was released on April 27, 2018.
- On May 2, 2018 the FDA received confirmation from the Arizona Leafy Greens Marketing Agreement that romaine lettuce was no longer being produced and distributed from the Yuma growing region, reducing the potential for exposure to contaminated product. At that time, due to the 21-day shelf life, we could not be certain that romaine lettuce from that region was no longer in the supply chain.
- On May 31, 2018 the FDA released a blog with updated information on our ongoing traceback investigation (for additional information, visit FDA Update on Traceback Related to the E. coli O157:H7 Outbreak Linked to Romaine Lettuce).
- The FDA is working closely with federal, state, and local partners on an ongoing traceback investigation to determine the source of romaine lettuce supplied to ill consumers. In a typical traceback effort, CDC and the FDA identify clusters of people who became ill, especially in different geographical regions and work to trace the food eaten by those made ill to a common source. For this outbreak investigation, we have been able to identify romaine lettuce as the common food source. Romaine products that would have caused illness were no longer available at exposure locations, making it difficult to determine production lots of concern. In addition, we have found that a single production lot may contain romaine from multiple ranches, which makes the traceback more challenging. We are working with federal and state partners and companies as quickly as possible to collect, review and analyze hundreds of records in an attempt to traceback the source of the contaminated romaine lettuce.
- To date, the available information indicates that romaine lettuce from the Yuma growing region is the source of the current outbreak of E. coli O157:H7 infections, and was supplied to restaurants and retailers through multiple processors, grower/shipper companies, and farms. The information we have collected indicates that the illnesses associated with this outbreak cannot be explained by a single grower, harvester, processor, or distributor. While traceback continues, FDA will focus on trying to identify factors that contributed to contamination of romaine across multiple supply chains. The agency is examining all possibilities, including that contamination may have occurred at any point along the growing, harvesting, packaging, and distribution chain before reaching consumers. (for additional information, visit FDA Update on Traceback Related to the E. coli O157:H7 Outbreak Linked to Romaine Lettuce).
- The traceback investigation is ongoing and additional information will be provided as it becomes available.
- From June 4 – June 8, 2018 sampling for the environmental assessment was conducted in the Yuma growing region.
- On June 28, 2018 the CDC announced that the outbreak has ended. In addition, the FDA and CDC announced preliminary sample results from the environmental assessment of the Yuma growing region.
E.coli O157:H7 is a Shiga-toxin-producing (STEC) E. coli. The symptoms of STEC infections vary for each person but often include severe stomach cramps and bloody diarrhea. If there is fever, it is usually not very high (less than 101 degrees Fahrenheit/less than 38.5 degrees Celsius). Most people get better within 5–7 days. Some infections are very mild, but others are severe or even life-threatening.
Around 5–10 percent of those who are diagnosed with STEC infection develop a potentially life-threatening complication, known as hemolytic uremic syndrome (HUS).
Symptoms of HUS include fever, abdominal pain, feeling very tired, decreased frequency of urination, small unexplained bruises or bleeding, and pallor. Most people with HUS recover within a few weeks, but some suffer permanent damage or die. People who experience these symptoms should seek emergency medical care immediately. Persons with HUS should be hospitalized because their kidneys may stop working (acute renal failure), but they may also develop other serious problems such as hypertension, chronic kidney disease, and neurologic problems.
• Cut leafy greens, including romaine lettuce, require time/temperature control for safety and should be refrigerated at 41°F or lower.
• Wash all lettuce