Category Archives: E.coli O157:H7

USA – State Fairs – E.coli O157 Outbreaks are common

Food Poisoning Bulletin

With the announcement yesterday of the MN State Fair E. coli outbreak that has sickened 11 people and hospitalized six, we were wondering how many other state and county fairs have had these serious outbreaks. Are these E. coli. outbreaks common at local, county, and state fairs?

  • In 2012, a huge E. coli outbreak linked to the Cleveland County Fair in North Carolina sickened 106 people, including 65 children. Thirteen people were hospitalized in that outbreak, and one child died. Fair organizers banned petting zoos at the event after this outbreak.
  • In 2014, another E. coli outbreak in Minnesota was linked to Zerebko Zoo Tran, a traveling petting zoo that goes from fair to fair during the summer months. At least 13 people were sickened in that outbreak.
  • In 2015, an E. coli outbreak associated with the Oxford County Fair in Maine sickened two children; one child died.
  • Also in 2015, an E. coli outbreak at the Red River Valley Fair in West Fargo, North Dakota sickened three children; one child developed hemolytic uremic syndrome (HUS), a type of kidney failure.
  • In 2016, an E. coli outbreak associated with the Washington County Fair in Oregon sickened at least two people.
  • In 2017, an E. coli outbreak at the Mesa County Fair in Grand Junction, Colorado sickened at least eight people.
  • Earlier this year, an E. coli outbreak at the San Diego County Fair sickened 10 people. Three people were hospitalized and one child died.

Research – Comparison of pH effects on ohmic heating and conventional heating for inactivation of Escherichia coli O157:H7, Salmonella enterica Serovar Typhimurium and Listeria monocytogenes in orange juice

Science Direct


Effect of pH on ohmic heating compared to conventional heating was investigated.

Adjusting pH has significant effect on the heating rate of ohmic heating.

Unusual tendency of pathogen inactivation was identified in ohmic heating.

Quality aspects of samples were not severely degraded regardless of pH.


The objective of the current study is to identify the influence of acidity on ohmic heating compared to conventional heating for inactivation of food-borne pathogensin orange juice. For conventional heating, the heating rate was not significantly different (P > 0.05) regardless of pH and pathogens were inactivated more effectively at lower pH. However, different patterns were observed for ohmic heating. Although temperature and electrical conductivity were not greatly affected by lowering pH, temperature increased more rapidly with increasing pH due to higher electrical conductivity. Also, the inactivation patterns were significantly different (P < 0.05) from conventional heating. While Salmonella Typhimurium was inactivated most rapidly at pH 2.5, Escherichia coli O157:H7 and Listeria monocytogenes were inactivated most rapidly at pH 4.5. When pathogens were exposed to each heating method at a fixed temperature, additional effects of ohmic heating were not observed. Also, the overall quality of orange juice subjected to ohmic heating was not greatly affected at any pH level. Therefore, increasing as well as lowering pH can also be considered effective ways to optimize pasteurization of orange juice when using ohmic heating. The different characteristics of ohmic heating compared to conventional heating indicate the necessity of a new approach.




Petting zoos may seem like the perfect opportunity to introduce kids to farm animals, but these creatures may possibly putting them in harm’s way of… germs. To what degree should parents be concerned? This past summer, a two-year-old child died after coming into contact with animals at the San Diego County Fair. Three other children under 13 reported contracting illnesses from the same location.

The source of the illness? E.Coli linked to contact with the fair’s animals.

Petting zoos are fairly popular. In summer and fall months, they’re a highlight at local fairs. Later in the year, they’re featured in festivals, pumpkin patches, schools, aquariums, even farmers’ markets. This family-friendly activity can turn dangerous when children come into contact with bacteria that causes serious illness.

According to the Centers for Disease Control and Prevention (CDC), “Every year, many people get sick after visiting an animal exhibit. From 2010-2015, about 100 outbreaks of illness in people linked to animals in public settings like zoos, fairs, and educational farms were reported to public health officials.”

UK – The bloody diarrhoea gives it away: UK family of boy hit by E. coli O157 after Turkish holiday takes legal action

Barf Blog

kswfoodworld E.coli O157

Image CDC


Julie Gilmartin, 39, said her son Matthew Bennett, 10, started to develop symptoms including diarrhea on the plane home from a week-long stay at the Bone Club Sunset Hotel & Spa, Antalya, at the start of July.

Following several tests, his mother was advised Matthew had been diagnosed with E.coli O157, a serious bacterial infection that can cause serious long-term complications and sometimes even death.

Research – Outbreak of Escherichia coli O157:H7 Infections Linked to Mechanically Tenderized Beef and the Largest Beef Recall in Canada, 2012

Journal of Food Protection


Contaminated beef is a known vehicle of Escherichia coli O157:H7 infection, although more attention is given to the control of E. coli O157:H7 in ground, rather than whole-cut, beef products. In September 2012, an investigation was initiated at an Alberta, Canada, beef plant after the detection of E. coli O157:H7 in two samples of trim cut from beef originating from this plant. Later in September 2012, Alberta Health Services identified five laboratory-confirmed infections of E. coli O157:H7, and case patients reported eating needle-tenderized beef steaks purchased at a store in Edmonton, Alberta, produced with beef from the Alberta plant. In total, 18 laboratory-confirmed illnesses in Canada in September and October 2012 were linked to beef from the Alberta plant, including the five individuals who ate needle-tenderized steaks purchased at the Edmonton store. A unique strain of E. coli O157:H7, defined by molecular subtyping and whole genome sequencing, was detected in clinical isolates, four samples of leftover beef from case patient homes, and eight samples of Alberta plant beef tested by industry and food safety partners. Investigators identified several deficiencies in the control of E. coli O157:H7 at the plant; in particular, the evaluation of, and response to, the detection of E. coli O157 in beef samples during routine testing were inadequate. To control the outbreak, 4,000 tons of beef products were recalled, making it the largest beef recall in Canadian history. This outbreak, in combination with similar outbreaks in the United States and research demonstrating that mechanical tenderization can transfer foodborne pathogens present on the surface into the interior of beef cuts, prompted amendments to Canada’s Food and Drug Regulations requiring mechanically tenderized beef to be labeled as such and to provide safe cooking instructions to consumers. A detailed review of this event also led to recommendations and action to improve the safety of Canada’s beef supply.

  • Mechanically tenderized beef steaks linked to E. coli O157 illnesses in Canada.

  • Largest beef recall in Canada underscores importance of plant-level E. coli controls.

  • Outbreak of E. coli O157 infections prompts food safety improvements in Canada.

Research -The combined effect of high pressure processing and dimethyl dicarbonate to inactivate foodborne pathogens in apple juice

Research Gate

Novel processing technologies can be used to improve both the microbiological safety and quality of food products. The application of high pressure processing (HPP) in combination with dimethyl dicarbonate (DMDC) represents a promising alternative to classical thermal technologies. This research work was undertaken to investigate the combined effect of HPP and DMDC, which was aimed at reaching over 5-log reduction in the reference pathogens Escherichia coli O157:H7, Salmonella enterica, and Listeria monocytogenes inoculated in apple juice. Different strains of each species were tested. The pressure (ranging from 100 to 600 MPa), dwell time (from 26 to 194 s), and DMDC (from 116 to 250 mg/L) were tested based on a central composite rotatable design. The dwell time, in the studied range, did not have a significant effect (p > 0.1) on the pathogens´ reduction. All treatments achieved a greater than 5-log reduction for E. coli O157:H7 and L. monocytogenes. The reductions for S. enterica were also greater than 5-log for almost all tested combinations. The results for S. enterica suggested that it is more resistant to HPP and DMDC compared with E. coli O157:H7 and L. monocytogenes. The findings of this study showed that DMDC at low concentrations can be added to apple juice to reduce the parameters conventionally applied in HPP. The combined use of HPP and DMDC was highly effective under the conditions of this study.

Research – Application of continuous-type pulsed ohmic heating system for inactivation of foodborne pathogens in buffered peptone water and tomato juice

Science Directl


The purpose of this study was to inactivate Escherichia coli O157:H7, SalmonellaTyphimurium, and Listeria monocytogenes by continuous-type pulsed ohmic heatingin buffered peptone water (BPW) and tomato juice. First, BPW inoculated with the three pathogens were treated at different flow rates (0.2–0.4 LPM) and treatment voltages (9.43–12.14 Vrms/cm). Both heating rate of BPW and reduction rates of pathogens increased corresponding to decreased flow rate. Accordingly, higher numbers of pathogens survived at a higher flow rate (0.4 LPM). Increasing treatment voltage was an effective way to inactivate pathogens at 0.4 LPM, but the heating rate overly accelerated with increasing voltage adversely affecting food quality. Alternatively, increasing initial temperature by preheating can help inactivate pathogens in the early treatment stage without affecting heating rate. From the BPW experiments, we identified that treatment conditions such as flow rate, voltage, and initial temperature are important factors determining pathogen inactivation performance of continuous-type ohmic heating. When applied to tomato juice, 5 log reductions of all three pathogens were achieved by applying 12.14Vrms/cm ohmic heating with 0.2 LPM flow rate after preheating sample to 50 °C with a water bath. Quality aspects of color and lycopene content were observed, and a and b values decreased after treatment. Because preheating with additional equipment is inconvenient and occupies valuable space, we developed sequential three cylinder type ohmic heating. By applying the developed sequential ohmic heating, 5 log reductions were achieved for all three pathogens without preheating under the same treatment conditions. Therefore, we concluded that sequential continuous-type ohmic heating can be used utizied effectively to control foodborne pathogensby the juice industry.