Category Archives: E.coli O157

Research – Risk Factors for Non-O157 Shiga Toxin–Producing Escherichia coli Infections, United States



Shiga toxin–producing Escherichia coli (STEC) causes acute diarrheal illness. To determine risk factors for non-O157 STEC infection, we enrolled 939 patients and 2,464 healthy controls in a case–control study conducted in 10 US sites. The highest population-attributable fractions for domestically acquired infections were for eating lettuce (39%), tomatoes (21%), or at a fast-food restaurant (23%). Exposures with 10%–19% population attributable fractions included eating at a table service restaurant, eating watermelon, eating chicken, pork, beef, or iceberg lettuce prepared in a restaurant, eating exotic fruit, taking acid-reducing medication, and living or working on or visiting a farm. Significant exposures with high individual-level risk (odds ratio >10) among those >1 year of age who did not travel internationally were all from farm animal environments. To markedly decrease the number of STEC-related illnesses, prevention measures should focus on decreasing contamination of produce and improving the safety of foods prepared in restaurants.

UK – Large rise of E. coli O26 infections noted in England

Food Safety News

An increase in a type of E. coli over the past decade has prompted scientists to warn of an emerging threat to public health in England.

While part of the rise is because of better detection of non-O157 Shiga toxin-producing E. coli (STEC) in labs, there is evidence more people are actually getting sick.

Researchers looked at STEC O26:H11 clonal complex (CC) 29 in England. Between January 2014 and December 2021, 834 human isolates from 724 patients belonging to CC29 were sequenced at the UK Health Security Agency (UKHSA).

STEC O26:H11 notifications in 2021 were eight times higher than those recorded in 2014. Diagnoses of STEC O26 in England have increased each year from 19 in 2014 to 144 in 2021. Most cases were female and the highest proportion belonged to the 0 to 5 age group, found the study in the Journal of Infection.

Hemolytic Uremic Syndrome (HUS) was diagnosed in 40 cases and three children died. HUS is a severe complication associated with E. coli infections that causes kidney failure.

USA – CORRECTION NOTICE: New Hampshire Laboratory Error Incorrectly Resulted in Recall of lēf Farms “Spice” Packaged Salad Greens: Recall Canceled – E.coli O157


Company Announcement

Concord, NH – The New Hampshire Department of Health and Human Services (DHHS) has determined that a laboratory error incorrectly caused last week’s recall announcement concerning lēf Farms “Spice” Packaged Salad Greens. The products from lēf Farms are safe and the recall has been canceled.

On May 5, a press release was issued regarding a potential contamination of Escherichia coli O157 bacteria of a specific lot of lēf Farms “Spice” Packaged Salad Greens. Upon being informed, lēf Farms voluntarily initiated a recall of the potentially affected products, prioritizing the health and safety of their customers. Subsequent whole genome sequencing was conducted, which determined that the control sample and the lēf Farms sample were nearly identical, indicating that the initial lab results were inaccurate due to a contamination error within the lab itself.

“I wish to apologize to lēf Farms, their customers and the public for this unfortunate event,” said Division of Public Health Services (DPHS) Director Tricia Tilley. “lēf Farms’ quick and decisive actions put the health of their customers first. Their products are safe for consumers. We appreciate that lēf Farms has been a willing partner in this process. While this situation is unprecedented, our dedicated staff will embrace all corrective actions to ensure it will not occur again.”

Shawn Jasper, State Commissioner of Agriculture, Markets and Food added: “After a two-day inspection of lēf Farms’ facility and products, what we discovered was a company that operates at the highest level of food safety and integrity. We are working closely with the FDA and lēf Farms to make this right.”

lēf Farms is a subsidiary of BrightFarms, a national leader in the booming indoor farming industry, which is transforming how produce is grown and delivered with its expanding network of high-tech, sustainable hydroponic farms.

“We are relieved to confirm that this was merely a lab mistake, and our product was never at risk. Customer health and safety remain our top priority. I’m immensely proud of our team’s swift response and effective collaboration with FDA and state officials,” said Steve Platt, CEO of BrightFarms.

With the recall canceled, lēf Farms “Spice” is returning to store shelves in Hannaford and Market Basket in Maine, Massachusetts, New Hampshire, New York, Rhode Island and Vermont. There is no longer any need for consumers who have purchased the lēf Farms “Spice” products to discard them or seek refunds from their place of purchase. Consumers with questions are encouraged to call lēf Farms at 1-866-857-8745 between 8:00am-6:00pm EDT or email with the subject line: Recall.

The PHL has not experienced a false positive from routine testing that resulted in a voluntary recall in more than twenty years. DHHS is working closely with the U.S. Food and Drug Administration (FDA) to confirm the source of the contamination and will implement necessary protocol changes to ensure it is not repeated. DHHS has been in communication with lēf Farms, the NH Department of Agriculture, Markets and Food, and the FDA. Based on the results of the investigation of the contaminated sample, the PHL will implement corrective actions to protect consumers, manufacturers and food producers, and the general public.

This is a correction to the press releaseExternal Link Disclaimer issued on May 4, 2023 with the headline: “lēf Farms Recalls “Spice” Packaged Salad Greens Because of Possible Health Risk.”

Original Press Release

Research -Climate change and food safety: Temperature impact on the attachment of Escherichia coli pathogroups on cress leaf

Wiley Online


Climate change and its worldwide effects are undeniable. Temperature increase due to climate change may affect foodborne pathogen survival on fresh produce. This study aimed to present an evaluation of climate change impact regarding temperature rise situations, on attachment of different pathogenic Escherichia coli strains on cress grown under controlled conditions. EHEC O157:H7, EAEC O104:H4 and EPEC O26 were inoculated with initial inoculum concentration of 8 log MPN/mL at different stages during growth to observe how inoculation time (7, 14, 21 and 28 days post sowing; dps) and route (seed and leaves) affect pathogen load on fresh produce. This study revealed that temperature increase designed according to mitigation scenarios for climate change (+2, +4 and +6 °C) did not cause any considerable change in pathogen persistence on leaf at 30 dps (~4.5 to 7 log MPN/g). In plants contaminated at later stage (21 and 28 dps), higher bacterial populations were obtained for all temperatures studied. Our results show that E. coli translocated towards leaf portions from seed and established significant amount of pathogen load on leaf (~4 to 5.3 log MPN/g). Also, inoculated bacteria have tightly bound to leaf (~3.5 to 7 log MPN/g) and cannot be eliminated by washing. Although persistence of E. coli O157:H7, O104:H4 and O26 did not differ significantly according to temperature, the bacterial load on the leaves was above infectious dose for humans.

USA – lēf Farms Recalls “Spice” Packaged Salad Greens Because of Possible Health Risk – E.coli O157


Company Announcement

lēf Farms of Loudon, N.H. is voluntarily recalling a single lot of the lēf Farms “Spice” Packaged Salad Greens (“best by” date 5/5/23, lot number SP10723- 1RGH1, UPC 8 50439 00709 1) produced in its Loudon, New Hampshire greenhouse because they have the potential to be contaminated with Escherichia coli 0157:H7 (E. coli) bacteria. According to the Food and Drug Administration (FDA), E. coli causes a diarrheal illness often with bloody stools. Although most healthy adults can recover completely within a week, some people can develop a form of kidney failure called Hemolytic Uremic Syndrome (HUS). HUS is most likely to occur in young children and the elderly. The condition can lead to serious kidney damage and even death.

The product comes in a 4- oz, clear, plastic clamshell container. Information about the “best by” date, lot number and UPC can be found at the bottom of the package. Pictures to assist customers in identifying the recalled products are found at the end of this announcement.

No illnesses have been reported to date. The recall was initiated when the New Hampshire Department of Agriculture received a positive test result for E. coli 0157:H7 in a single package of lēf Farms “Spice” Packaged Salad Greens (4 oz) as part of routine testing.

lēf Farms “Spice” is the only product impacted to date and affected retailers include Hannaford and Market Basket in Maine, Massachusetts, New Hampshire, New York, Rhode Island and Vermont.

In addition to today’s voluntary recall, the company is proactively testing all products produced in its New Hampshire facility for E. coli 0157:H7 prior to distribution.

Retailers have been instructed to remove all recalled products from store shelves. Consumers who have purchased the affected lēf Farms “Spice” products should discard them or present a photo of the product or receipt to their place of purchase for a full refund and then discard.

Consumers with questions are encouraged to call 1-866-857-8745 between 8:00am-7:00pm EDT or email with the subject line: Recall.

Company Contact Information

lēf Farms

Product Photos

Netherlands – Safety warning Hema fricandeau -E.coli O157


Hema warns against the Hema fricandeau. E-Coli O157 was found in the Hema fricandeau. Contamination with this bacteria can cause stomach and intestinal complaints. Do not eat the product!

See the Hema website.

Which product is this?

  • Hema fricandeau
  • Item number: 27906111
  • Sales period: March 31, 2023 – April 7, 2023

Yours sincerely

The Dutch Food and Consumer Product Safety Authority

Research – Microbiological Risk Assessment in Foods: Background and Tools, with a Focus on Risk Ranger


Risk assessment is an important phase of the food production path; it is strictly related to the processing chain as a necessary step for safe foods. This paper represents a contribution to understanding what is and how risk assessment could be conducted; it aims to provide some information on the structure of risk assessment, the tools for its identification and measurement and the importance of risk assessment for correct communication. In this context, after a focus on the background and on some commonly used tools (Risk Ranger, FDA-iRisk, decision tree, among others), the paper describes how to perform risk assessment through three case studies: lettuce (for Listeria monocytogenes), chicken salad (for Escherichia coli), and fresh egg pasta (for Staphylococcus aureus) in the first step, and then a comparison of risk for chicken salad contaminated by different pathogens (E. coli O157:H7, Campylobacter spp. and Salmonella sp.). As a final step, a critical evaluation of Risk Ranger was carried out, pointing out its pros and cons.

Research – Detection of Escherichia coli O157:H7 in imported meat products from Saudi Arabian ports in 2017

Escherichia coli O157:H7 is a foodborne pathogen, which causes various health conditions in humans, including fatigue, nausea, bloody diarrhoea and in some cases, even death. In 2017, 15.71% of the total imported food products in Saudi Arabia (SA) were meat-based. India and Brazil are two of the top five countries from where SA imports meat. According to the Saudi Food and Drug Authority, in 2017, at least 562, 280, and 50 samples of imported beef, chicken and sheep meat, respectively, were tested for the presence of E. coli O157:H7. Amongst these, E. coli O157:H7 was detected in respectively 6.80% and 2.20% of the tested beef meat samples imported from India and Brazil as well as in respectively 6.96% and 3.57% of the tested chicken samples imported from Brazil and Ukraine. Moreover, the pathogen was detected in 2.13% of the tested sheep meat samples imported from India. The present report provides evidence that imported meat can serve as the carrier of E. coli O157:H7, which may lead to epidemics within the Kingdom of Saudi Arabia.

USA – USDA Starts Testing Ground Beef For Big Six E. coli Strains, O157

Food Poisoning Bulletin

The USDA’s Food Safety and Inspection Service (FSIS) has started testing ground beef, bench trim, and other raw ground beef components for Shiga toxin-producing E. coli strains (STEC) that are adulterants. They include the “Big Six” O26, O45, O103, O111, O121, and O145 as well as O157. The testing started on February 1, 2023. This new program was announced in the Federal Register on June 4, 2020.

USA – Persistent Strain of E. coli O157:H7 (REPEXH01) Linked to Multiple Sources



REPEXH01 is a persistent strain of Shiga toxin-producing E. coli O157:H7 bacteria that has caused illnesses and outbreaks in the United States.

Illness caused by this strain was first reported to PulseNet in 2017. Illnesses caused by this strain occur year-round but are less common in winter.

In the past, the REPEXH01 strain has spread to people through contaminated food and contaminated recreational water.

This strain is relatively diverse genetically. Bacteria in this strain are within 21 allele differences of one another by whole genome sequencing, which is more diverse than typical multistate foodborne outbreaks where bacteria generally fall within 10 allele differences of one another.

Identified outbreak sources*

*Confirmed sources were implicated by epidemiologic
plus traceback or laboratory data. Suspected sources
were implicated by epidemiologic data only. More info

  • Recreational water (confirmed): 1 outbreak
  • Romaine lettuce (confirmed): 1 outbreak
  • Leafy greens (suspected): 1 outbreak
  • Ground beef (suspected): 2 outbreaks