Around 80 people got food poisoning from a pasta meal at a soccer tournament this past month in Sweden.
An investigation into the incident in Gammelstad on Aug. 5 revealed people fell ill after eating spaghetti bolognese from a restaurant in the city of Luleå.
An investigation by officials from Luleå Municipality to determine the cause included studying the symptoms of those affected, interviewing patients, visiting the food company and sampling leftovers.
Food had been prepared at a restaurant the day before the event and stored in a refrigerator. On Aug. 5, it had been reheated for transporting to and serving at the tournament.
Bacillus cereus and Staphylococcus aureus
Testing of the bolognese left at the restaurant was found to be satisfactory. Samples were also taken in Gammelstad where serving took place. High levels of bacteria were detected in the pasta, plus the presence of toxins that can cause food poisoning. Food had been left at room temperature for some time after serving, which provided an opportunity for bacterial growth.
Bacillus cereus and Staphylococcus aureus were found in the pasta meal. Symptoms experienced by those sick matched what would be expected with such contamination.
Staphylococcal food poisoning is caused by eating foods contaminated with toxins produced by the Staphylococcus aureus bacteria. If this bacteria ends up in food that is stored at the wrong temperature for too long, it can multiply and form a heat-resistant toxin that can make people sick.
Based on the short period from when food was delivered to people eating it, officials said it was likely that bacteria were present before delivery. However, from information provided by the restaurant it was not possible to pin down how such bacterial and toxin growth occurred.
To increase knowledge about such outbreaks, follow-up analyses will be carried out at Livsmedelsverket (the Swedish Food Agency) and further controls of the business will be done by authorities.
Histamine in fish again
Meanwhile, 20 people fell sick recently in Sweden due to histamine levels in fish. The foodborne outbreak was linked to tuna from Vietnam.
In April 2021, 19 people were affected by histamine poisoning in Stockholm after eating tuna loins from Vietnam at three different restaurants.
In 2020, there were three outbreaks of histamine poisoning in tuna from Vietnam in three months. These incidents affected about 60 people but contaminated tuna came from different batches. Patients were from different areas in southern and central Sweden.
Onset of histamine food poisoning symptoms can range from minutes to several hours following ingestion of the toxin. Typically, the average incubation period before illness is one hour.
The most common symptoms of histamine, also known as scombroid fish poisoning, are tingling or burning sensation in the mouth, facial swelling, rash, hives and itchy skin, nausea, vomiting or diarrhea. They usually resolve within several hours without medical intervention.
Production of histamine is related to mishandling of food because of storage at incorrect temperatures. Once produced, histamine cannot be eliminated by normal cooking or freezing temperatures.
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