A suspected Clostridium perfringens outbreak affected 30 people in Greece in 2021, according to a study.
In May 2021, several cases of gastroenteritis were reported among students and staff at a secondary school on a Greek island. Daily hot lunches were delivered by a catering company and consumed in the classrooms.
At the end of May, a regional unit of the Hellenic Food Authority (EFET) informed the Greek National Public Health Organization about a cluster of gastroenteritis cases among students and teachers aged 12-18. The school is in a small town on a remote Greek island in the northeastern Aegean, which had limited capacity for specific laboratory tests.
Patient and food sampling
Based on a questionnaire, the researchers received 129 responses from students and staff and identified 30 patients, four of whom were teachers. 60% of the cases were women, and the median age was 13 years with a range of 12 to 40 years.
Most of the patients had abdominal pain and diarrhea, while 19 reported fatigue. The median duration of symptoms was one day, with a maximum of three days, and no one was hospitalized.
Of 11 significant foods in the analysis, the consumption of spaghetti with ground (minced) meat was associated with the appearance of gastroenteritis, as found in the study published in the journal Pathogens and Foodborne Illnesses.
Clostridium perfringens was detected in two of the stool samples from three students. Six samples of spaghetti with ground beef were positive for Clostridium perfringens and four were also positive for Bacillus cereus. The whole and intact prepackaged food was found in the school refrigerator and was part of the food offered the day before, moments before the occurrence of the cases.
Investigation for Clostridium perfringens toxins in clinical and food samples was not performed due to lack of laboratory capacity, thus the pathogen behind the outbreak was not confirmed.
Food sampling and additional inspection of the two facilities involved were carried out by the EFET-Regional Directorate of the North Aegean Sea. The first was the school where the food was delivered and the second was the establishment where the food was produced before.
Research in school and catering.
Deficiencies were identified in the reception and distribution of meals, by the catering company and the reception committee at the school. The mass caterer did not accurately describe the type of lunch dishes on the delivery notes and the temperature of the meals was not verified on the receipt.
It was not specified if the time elapsed between the preparation and the consumption of the school lunches was less than two hours.
The environmental investigation revealed non-compliance around food staff training and implementation of the Hazard Analysis Critical Control Point (HACCP) plan at the food establishment.
Raw, marinated, blanched, and frozen ground beef was supplied in a blast freezer until recooked five days later. The spaghetti was then cooked and mixed with ground meat, transported and served at the school.
After cooking, the meals were packaged in individual portions and placed in a warm holding chamber. They were temporarily stored until all portions were ready to be loaded onto transport vehicles and placed in isothermal boxes.
Although the temperature in the chamber was supposed to be 75 degrees C (167 degrees F), during the investigation it was around 55 degrees C (131 degrees F).
No other outbreaks were linked to the caterer. Part of the same batch of ground beef was prepared and served a few days later at another location with no reported problems, suggesting mishandling occurred during the production of the meals or their distribution to the school, the study found.
Changes were applied to the reception and distribution of meals at the school. Recommendations to the catering establishment covered proper employee training and HACCP issues, especially with regard to temperature/time controls during all stages of production, handling, and distribution.
Laboratory capacity to detect bacterial toxins in the country and implementation of food safety measures in school settings should be strengthened, the researchers said.
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