Category Archives: STX 2

Research – Detection, Isolation, and Characterization of Shiga Toxin–Producing Escherichia coli in Flour

Journal of Food Protection

Wheat flour has recently been described as a novel vehicle for transmission of Shiga toxin–producing Escherichia coli (STEC). Very recently, an outbreak of STEC O121 and STEC O26 infections was linked to flour in the United States. The aim of the present study was to generate baseline data for the occurrence of STEC in flour samples from different retailers in Switzerland. In total, 70 flour samples were analyzed. After enrichment, the samples were screened for stx1 and stx2 by the Assurance GDS MPX ID assay. STEC strains were isolated and serotyped by the E. coli SeroGenoTyping AS-1 kit. The determination of stx subtypes was performed with conventional PCR amplification. Screening for eae, aggR, elt, and estIa/Ib was performed by real-time PCR. Nine (12.9%) of the flour samples tested positive for stx by PCR. STEC was recovered from eight (88.9%) of the positive samples. Two isolates were STEC O11:H48 harboring stx1c/stx1d, two were O146:H28 containing stx2b, one was O103:H2 containing stx1a and eae, and three were O nontypeable: Ont:H12 (stx2a), Ont:H14 (stx2a/stx2g), and Ont:H31 (stx1c/stx1d). STEC O103 belongs to the “top five” serogroups of human pathogenic STEC in the European Union, and STEC O146 is frequently isolated from diseased humans in Switzerland. Our results show that flour may be contaminated with a variety of STEC serogroups. Consumption of raw or undercooked flour may constitute a risk for STEC infection.

RASFF Alert – STEC E.coli – Chilled Lamb Meat


RASFF-enteropathogenic Escherichia coli (stx2- /25g) in chilled lamb meat from the United Kingdom in the Netherlands

RASFF Alert – STEC E.coli – O26 – Raw Goats Milk Cheese


RASFF -enteropathogenic Escherichia coli (026H11 eae+, stx-) in raw goat’s milk cheese from France in France

RASFF Alerts – STEC E.coli – Cheese – Lamb Ribs


RASFF -shigatoxin-producing Escherichia coli (presence /25g) in cheese from Italy in Italy

RASFF-shigatoxin-producing Escherichia coli (STEC stx1-; stx2-) in lamb ribs from the United Kingdom in the Netherlands

RASFF Alert- STEC E.coli – E.coli – Staphylococcus aureus – Raw Milk Soft Cheese


RASFF -shigatoxin-producing Escherichia coli (stx1+; stx2+; aea+) and Staphylococcus aureus (47000 CFU/g) and high count of Escherichia coli (60000 CFU/g) in soft cheese made from raw milk from France

Research – Investigation into an outbreak of Shiga toxin producing Escherichia coli (STEC) O157 PT 21/28 Stx2 in England, August 2017 – Raw Pet Foods


In August 2017, a cluster of 4 cases infected with genetically related strains of STEC O157 was identified. The strains possessed the stx2a toxin subtype, a toxin type known to be associated with more severe disease and the development of Haemolytic Ureamic Syndrome (HUS), a serious complication of this infection, predominantly affecting the kidneys. One case had died following development of HUS.

A multi-agency investigation was undertaken which included re-interviewing cases and the sampling and testing of implicated products. Interviews indicated that 3 of the cases had been exposed to dogs fed on a raw meat based diet), specifically, tripe. In 2 cases, the tripe has been purchased from the same supplier.

While one case was not linked to raw pet food, as cattle and sheep are the main reservoir of STEC in the UK, exposure to the same strain of STEC may have occurred through a different route. This may be indirect or direct exposure to the infected animals which entered the pet feed supply chain for example. Alternatively, the case may have been exposed to an animal fed a raw meat based diet without being aware of, or being able to recall that exposure.

Sampling and microbiological screening of raw pet food was undertaken and indicated the presence of STEC in the products. STEC was isolated from one sample of raw tripe but was different to the strain causing illness in the humans. Nevertheless, isolation of STEC did provide evidence for microbiological contamination of tripe and its pathogenic risk to human health and that it was a plausible transmission route in this outbreak. This adds to the evidence of raw pet food as a risk factor for zoonotic transmission of GI pathogens, which is already relatively widely accepted for salmonella, listeria and campylobacter.

Feeding raw meat based diet to companion animals has recently increased in popularity due to both increasing availability and beliefs that they provide health benefits to animals. Although still rare, an increase in STEC cases reporting exposure to raw meat based diet ’s was detected in 2017. There has also been an increased frequency of raw pet food incidents in 2017, suggesting an increasing trend in potential risk to humans from raw pet food. IMT concluded that the best approach to reduce the risk of infection is to improve awareness of risk and promote good hygiene practices amongst the public when handling raw pet food.


RASFF Alert – STEC E.coli -Chilled Beef – Sprouts – Sunflower Seeds -Boneless Beef


RASFF-shigatoxin-producing Escherichia coli (stx1+ /25g) in chilled beef from Argentina in the Netherlands

RASFF-shigatoxin-producing Escherichia coli (stx2+ /25g) in chilled beef from Argentina in the Netherlands

RASFF-shigatoxin-producing Escherichia coli (stx2+ /25g) in chilled beef from Argentina in the Netherlands

RASFF-shigatoxin-producing Escherichia coli (presence /25g) in sprouts from Germany, with raw material from Italy in Germany

RASFF-shigatoxin-producing Escherichia coli (presence /25g) in sunflower seeds from Bulgaria, packaged in Italy in Italy

RASFF-shigatoxin-producing Escherichia coli (stx2+) in chilled boneless beef striploin from Argentina in the Netherlands