An investigation into a fatal Bacillus cereus outbreak linked to a restaurant in Germany has highlighted temperature and storage issues.
Eleven cases were reported with five hospitalizations, and one death. The outbreak was likely caused by contaminated pre-cooked tortellini with a meat filling.
There is no reporting obligation for Bacillus cereus under the German Infection Protection Act (IfSG) but food poisoning and infectious gastroenteritis must be reported if the affected person works in food processing or if there is a link between two or more human cases.
In September 2024, two people fell ill after eating at a restaurant. One person suffered severe vomiting, sweating and diarrhea, about 190 minutes after eating meat-filled tortellini with ground (minced) meat and cheese cream sauce. They were hospitalized and, after receiving treatment, were symptom-free 48 hours later.
The second person fell ill with nausea and vomiting, the same time after eating meat-filled tortellini with ham and cheese cream sauce, and diarrhea two hours later. After a brief improvement, fever occurred 20 hours after eating and hospitalization followed. This patient died the following day, about 50 hours after visiting the restaurant.
Testing proved that Bacillus cereus was present in the restaurant environment six days before these two patients consumed the tortellini.
Severe illnesses
In the next few days, several more patients who had eaten at this restaurant between the end of August and beginning of September were reported. Out of nine other patients, three were hospitalized with severe symptoms. These included gastrointestinal issues including vomiting, circulatory problems, and in some cases diarrhea, as well as complications such as liver failure and kidney dysfunction, according to a study published in the International Journal of Food Microbiology.
Pre-cooked meat-filled tortellini had a musty, sour odor. Scientists said this calls into question hygiene and temperature management onsite. A high bacterial count of Bacillus cereus was detected in food and environmental samples from the restaurant as well as in the stool of one hospitalized person.
Seventy isolates from food, food packaging, kitchen utensils and the environment and a stool sample were analyzed. This revealed 56 outbreak-associated isolates.
Outbreak strain in the environment
Bacillus cereus with emetic toxin-forming capacity was found in swab samples from the production environment and on cleaning utensils with a very close genetic relationship to isolates from foods associated with the outbreak and the stool sample.
Pre-cooked meat-filled tortellini was heavily contaminated with Bacillus cereus, which had produced a high level of the emetic toxin cereulide. Analyzed tortellini was prepared after the deceased person had eaten in the restaurant but evidence from the patient’s stool shows that the pathogen was ingested in large quantities with food.
It is thought that the pathogen was introduced from the production environment. There were also possible errors in temperature management or storage duration of tortellini, with indications that it was not consistently stored at low temperatures.
The business was shut by the operator voluntarily. After investigation results were sent to authorities, the outlet was closed and deregistered. Before a new restaurant was allowed to open on the premises, cleaning and disinfection by a specialist company was ordered and official swab samples were taken from the environment. Following negative results for Bacillus cereus, the new owners were permitted to open.
