Category Archives: STEC

Research – Survey of Intact and Nonintact Raw Pork Collected at Retail Stores in the Mid-Atlantic Region of the United States for the Seven Regulated Serogroups of Shiga Toxin–Producing Escherichia coli

Journal of Food Protection

ABSTRACT

A total of 514 raw pork samples (395 ground or nonintact and 119 intact samples) were purchased at retail stores in Pennsylvania, Delaware, and New Jersey between July and December 2017. All raw pork samples were screened for serogroup O26, O45, O103, O111, O121, O145, or O157:H7 cells of Shiga toxin–producing Escherichia coli (STEC-7) using standard microbiological and molecular methods. In short, 21 (5.3%) of the 395 ground or nonintact pork samples and 3 (3.4%) of the 119 intact pork samples tested positive via the BAX system real-time PCR assay for the stx and eae virulence genes and for the somatic O antigens for at least one of the STEC-7 serogroups. However, none of these 24 presumptive-positive pork samples subsequently yielded a viable isolate of STEC displaying a STEC-7 serogroup-specific surface antigen in combination with the stx and eae genes. These data suggest that cells of STEC serogroups O26, O45, O103, O111, O121, O145, or O157:H7 are not common in retail raw pork samples in the mid-Atlantic region of the United States.

HIGHLIGHTS
  • None of the 514 retail raw pork samples were positive for STEC-7.

  • Four of 514 raw pork samples harbored E. coli of unknown serogroup containing stx and eae.

  • STEC-7 are uncommon in retail raw pork samples in the U.S. mid-Atlantic region.

 

RASFF Alert – STEC E.coli – Frozen VP Buffalo Sausages

RASFF-Logo

RASFF – shigatoxin-producing Escherichia coli (stx1+ stx2+ /25g) in frozen vacuum-packed buffalo sausages from Belgium in the Netherlands

Research – Antibiofilm Efficacy of Peptide 1018 against Listeria monocytogenes and Shiga Toxigenic Escherichia coli on Equipment Surfaces

Journal of Food Protection

ABSTRACT

Listeria monocytogenes and Shiga toxigenic Escherichia coli (STEC) are important foodborne bacterial pathogens that can form biofilms on equipment surfaces at food processing facilities. Pathogens in biofilms are resistant to conventional antimicrobials and require higher antimicrobial concentrations to be inactivated. In this study, the efficacy of a synthetic innate defense regulator peptide 1018 (peptide 1018) for inactivating L. monocytogenes and STEC (O26, O111, O145, O157) biofilms on stainless steel and polycarbonate surfaces was investigated. Stainless steel and polycarbonate coupons (12 mm in diameter) were used in a Centers for Disease Control and Prevention biofilm reactor containing 400 mL of 10% tryptic soy broth (TSB) that had been inoculated with an individual strain of L. monocytogenes or STEC to obtain 6 log CFU/mL populations. The reactor was set with a constant flow rate at 50 mL/h of 10% TSB for 48 h. After 48 h, coupons were treated with peptide 1018 at 0, 10, 20, or 50 μg/mL in phosphate buffer saline (PBS) for 24 h. Surviving bacterial populations were determined by scraping off the coupons and spiral plating on selective media. Significantly higher levels of pathogens in biofilms formed by certain bacterial strains, including L. monocytogenes F6854, E. coli O157:H7 RM4407 and NADC5713, and non-O157 E. coli NADC3629, were recovered on polycarbonate surfaces than on stainless steel. Antibiofilm efficacy of peptide 1018 against pathogens was concentration-dependent and varied with the type of pathogen and material surfaces. Peptide 1018 at 50 μg/mL significantly inactivated all tested bacterial biofilms on both surfaces compared with the PBS control (P < 0.05). L. monocytogenes was the bacterium most sensitive to peptide 1018; on stainless steel surfaces treated with 50 μg/mL peptide 1018, there was a 3.7- to 4.6-log CFU/cm2 reduction in Listeria populations compared with a 1.0- to 3.5-log CFU/cm2 reduction of STEC. Results suggest that peptide 1018 may be used to inactivate L. monocytogenes and STEC biofilms on equipment surfaces.

HIGHLIGHTS
  • Bacteria attach at higher levels on polycarbonate surfaces than on stainless steel.

  • L. monocytogenes is more sensitive than STEC to peptide 1018.

  • Peptide 1018 can be used to inactivate biofilms on equipment surfaces.

Research – Outbreaks of Shiga Toxin–Producing Escherichia coli Linked to Sprouted Seeds, Salad, and Leafy Greens: A Systematic Review

Journal of Food Protection

ABSTRACT

Shiga toxin–producing Escherichia coli (STEC) outbreaks involving ready-to-eat salad products have been described in the scientific literature since 1995. These products typically do not undergo a definitive control step such as cooking to eliminate pathogens. To reduce the number of STEC infections from salad products, efforts will need to focus on preventing and reducing contamination throughout the food chain. We performed a systematic review of STEC outbreaks involving sprouted seeds, salad, or leafy green products to determine whether there were recurrent features, such as availability of microbiological evidence or identification of the contamination event, which may inform future investigations and prevention and control strategies. Thirty-five STEC outbreaks linked to contaminated leafy greens were identified for inclusion. The outbreaks occurred from 1995 to 2018 and ranged from 8 to more than 8,500 cases. Detection of STEC in the food product was rare (4 of 35 outbreaks). For the remaining outbreaks, the determination of leafy greens as the source of the outbreak mainly relied on analytical epidemiology (20 of 35) or descriptive evidence (11 of 35). The traceback investigation in 21 of 32 outbreaks was not able to identify possible routes leading to where the STEC bacteria came from or how the leaves were contaminated. Investigations in eight outbreaks found poor practice during processing that may have contributed to the outbreak, such as insufficient postharvest disinfection of the product. Six outbreak investigations were able to identify the outbreak strain in animal feces near the growing fields; two of these were also able to find it in irrigation water on the farms, providing a likely route of contamination. These results highlight the limitations of relying on microbiological confirmation as a basis to initiate investigations of upstream production to understand the source of contamination. This review also demonstrates the importance of, and difficulties associated with, food-chain traceback studies to inform control measures and future prevention.

HIGHLIGHTS
  • Systematic review identified 35 STEC outbreaks linked to contaminated leafy greens.

  • Most (20 of 35) outbreaks relied on epidemiological evidence to identify leafy greens.

  • In 21 of 35 studies, no evidence was found for how original contamination occurred.

  • In 11 studies, water was identified as the probable vector in the contaminating product.

  • Only two studies were able to identify the likely source and route of contamination.

USA – FDA Partners with the University of Arizona, Wellton-Mohawk Irrigation and Drainage District, and Yuma Area Leafy Greens Stakeholders to Enhance Food Safety

FDA

The U.S. Food and Drug Administration has launched a new initiative with support from the Arizona Department of Agriculture, and in conjunction with the University of Arizona Cooperative Extension, the Wellton-Mohawk Irrigation and Drainage District (WMIDD), and members of the Yuma area leafy greens industry to better understand the ecology of human pathogens in the environment in the Yuma agricultural region. This initiative will be a multi-year study which will focus on how these pathogens survive, move and possibly contaminate produce prior to harvest.

The launch of this initiative follows the largest E.coli O157:H7 outbreak in the United States since 2006. The outbreak, which was linked to romaine lettuce grown in the Yuma region, began in the spring of 2018 and resulted in 210 reported illnesses from 36 states, 96 hospitalizations, 27 cases of hemolytic uremic syndrome (HUS) and five deaths. In response,  FDA led an Environmental Assessment (EA) of the Yuma produce growing region in collaboration with Centers for Disease Control and Prevention (CDC), the Arizona Department of Agriculture (AZDA), WMIDD, and state partners from June through August 2018.

While the EA was useful in narrowing the scope of the outbreak, many questions remain unanswered regarding the specific origin of the pathogen, the environmental distribution, and potential reservoirs for the outbreak strain. The findings made clear that further collaboration among leafy greens stakeholders and FDA is needed to better understand potential sources of microbial contamination, the prevalence and persistence of human pathogens in the ecosystem near growing areas, and the best management practices to prevent future outbreaks from occurring.

Throughout this initiative, FDA will work in partnership with water quality, food safety, and agricultural experts from the University of Arizona Cooperative Extension, representatives from the WMIDD, and members of the Yuma area leafy greens industry. Research teams will be collecting and examining samples from the environment such as surface waters, canal sediment, and dust. The team will also be collecting scat samples to assess the impact that animal intrusion and native wildlife may have on the growing environment.

Shiga Toxin-Producing E.coli (STEC), of which E.coli O157:H7 is a strain, causes roughly 170,000 people to become ill every year. This generally happens through the consumption of contaminated food or water, or close contact with STEC-infected animals. Between 2009 and 2017, FDA and our partners at CDC identified 28 foodborne STEC outbreaks with known or suspected links to leafy greens. Like a lot of fresh produce, leafy greens are often eaten raw without a kill-step, such as cooking, that could eliminate pathogens that may be present.

The Yuma agricultural region, which encompasses Yuma County in Arizona and the Imperial Valley in California, is a leader in the production of leafy greens in the United States. The findings from this study will contribute new knowledge on how various environmental factors may influence bacterial persistence and distribution in this region, and how those factors may impact the risk of this commodity becoming contaminated. Results from this collaboration will lead to improved practices to prevent or mitigate food safety risks, and ultimately enhance the safety of produce grown in the region.

For More Information

USA – Surveillance for Foodborne Disease Outbreaks, United States, 2017 Annual Report

CDC

  • Highlights
  • In 2017, 841 foodborne disease outbreaks were reported, resulting in 14,481 illnesses, 827 hospitalizations, 20 deaths, and 14 food product recalls.
  • Norovirus was the most common cause of confirmed, single-etiology outbreaks, accounting for 140 (35%) outbreaks and 4,092 (46%) illnesses. Salmonella
    was the next most common cause, accounting for 113 (29%) outbreaks and 3,007 (34%) illnesses, followed by Shiga toxin-producing Escherichia coli, which caused 19 (5%) outbreaks and 513 (6%) illnesses, and Clostridium perfringens, which
    caused 19 (5%) outbreaks and 478 (5%) illnesses.
  • Mollusks (41 outbreaks), fish (37), and chicken (23) were the most common single food categories implicated. The most outbreak associated illnesses were from turkey (609 illnesses), fruits (521), and chicken (487).
  • As reported in previous years, restaurants (489) outbreaks, 64% of outbreaks for which a single location of preparation was reported), specifically
    restaurants with sit-down dining (366, 48%), were the most commonly reported locations of food preparation associated with outbreaks.

USA – Outbreak Investigation of E. coli Linked to Ground Bison from Northfork Bison Distributions, July 2019

FDA

September 13, 2019

The U.S. Food and Drug Administration (FDA), along with the Centers for Disease Control and Prevention (CDC), state and local partners in the U.S., and with the support of the Canadian Food Inspection Agency (CFIA), investigated a multistate outbreak of E. coli O121 and E. coli O103 illnesses likely linked to ground bison supplied by Northfork Bison Distributions Inc. of Saint-Leonard, Québec, Canada.

On September 13, 2019, CDC announced that the outbreak appears to be over.

During the investigation, FDA and CDC analyzed traceback and epidemiological information to determine that ground bison supplied by Northfork Bison Distributions Inc. was the likely cause of the illnesses. FDA laboratory analysis of bison patties packed by the firm on February 26th, 2019, confirmed the presence of one of the outbreak strains of E. coli.

Northfork Bison Distributions Inc. was forthcoming with information to aid in the investigation, and publicly announced a voluntary recall on July 16, 2019. This recall included ground bison meat and bison patties produced between February 22 and April 30, 2019.

FDA regulates bison meat because the authority is not assigned specifically to the United States Department of Agriculture’s (USDA) Food Safety Inspection Service (FSIS) in the Federal Meat Inspection Act (FMIA).

Recommendation

Because the product is frozen and may still be in freezers, distributors, retailers and restaurants should not distribute, use or serve ground bison (including bison burgers) recalled by Northfork Bison Distributions Inc.

Consumers should not eat products prepared using recalled ground bison (including bison burgers) sold under the Northfork Bison label including bison burgers sold to retailers in 4 x 4-ounce packages with expiration dates through October 8, 2020.

Buffalo Burger Canadian Bison Meat

RASFF Alerts – STEC E.coli – Frozen Beef

Last two weeks catch up

RASFF-Logo

RASFF – shigatoxin-producing Escherichia coli (stx1+ /25g) in frozen boneless beef topside from Brazil in the Netherlands

RASFF – shigatoxin-producing Escherichia coli ( stx2+ eae-; stx2+ eae+ present /25g) in frozen beef from Uruguay in Finland

Denmark – ‘No outbreak’: Danish medic after two children die from E. Coli STEC/VTEC complications

The Local

Two children – one on the island of Funen and another in the Copenhagen area – died due to a rare complication related to VTEC, a strain of the E. Coli bacteria.

Both children died of kidney failure, but the two tragic cases are not connected. A third child also contracted kidney failure but survived, DPSA said.

A consultant doctor and head of department at Copenhagen infectious disease research institute SSI stressed that the cases were not evidence of an outbreak and that the number of cases was not improbable.

“At this time, we have knowledge of three cases of kidney failure from August to September. That is not more than we would expect at this time of year. Fortunately there is nothing to suggest they are connected,” Tyra Grove Krause said.

 

France – E. Coli Bacteria: Chaource Lincet and Gaugry Raw Milk Cheeses Recalled – STEC E.coli O111:H8

Teller Report

A few hundred Chaource raw milk cheese brands Lincet and Gaugry, sold throughout France, are subject to a recall procedure after the demonstration of the presence of Escherichia coli. A check has highlighted in these products, manufactured by the Lincet cheese factory in Vaudes in the Aube, the presence of Escherichia coli O111: H8, indicates the cheese Friday in a statement.