Norwegian officials have solved a Bacillus cereus outbreak that affected more than 20 young children.

Several infants aged 5 to 6 months old became ill between November 2023 and January 2024 after eating a type of porridge.

Tveter Gård Foredling withdrew several Den Sorte Havre branded products aimed at children in January. Items were sold at Meny stores across the country. After this action, no further cases have been reported.

The Norwegian Food Safety Authority (Mattilsynet) received 23 reports of children falling sick and vomiting after eating products from Den Sorte Havre.

The Norwegian Food Safety Authority, the manufacturer, the Veterinary Institute, the Norwegian Institute of Public Health (FHI), and the Norwegian University of Life Sciences (NMBU) all worked on the possible reasons why children were ill.

Unusual outbreak
Laboratory testing was done on samples taken from products at the homes of affected families. Investigations discovered toxins produced by Bacillus cereus. In some samples, the amount was high enough to cause the symptoms experienced by children. The common ingredient in implicated products was black oats from the same raw material batch.

“This outbreak is unusual, as we know which foodstuff has made these children ill, but have had to search for why the food caused illness. Usually, it is the other way around; we search for food contaminated with the infectious agent the patients have become ill from,” said Taran Skjerdal, senior researcher in food safety at the Veterinary Institute.

Efforts are ongoing with the company to find out wher bacterial toxins may have formed in the production process.

Under the right conditions, Bacillus cereus can multiply in grains and foodstuffs, as it produces spores highly resistant to heat. Spores will grow under certain conditions and toxins can develop. Usually, Bacillus cereus food poisoning causes vomiting shortly after ingesting contaminated products and lasts up to a day.

Sick children have recovered.
Interviews of 12 parents by FHI revealed that children who fell ill vomited repeatedly one to two hours after eating the products. One child was a few months older than the others and did not vomit but had diarrhea after eating the product.

Sick children live in eight different parts of the country. Cases had eaten from three of five products aimed at children from Den Sorte Havre. Ten children had contact with health services due to their symptoms, but none were admitted to hospital. All of them have now recovered.

Symptoms described in the children were similar to those caused by other toxin-producing bacteria such as Staphylococcus aureus and Clostridium perfringens. The latter was ruled out because the toxin it forms cannot withstand the heat with which grain is treated before milling.

Scientists discovered toxins from Bacillus in several samples, but there were indications of toxins from Staphylococcus in one sample.

The Norwegian Food Safety Authority asked consumers to throw the recalled products away or to return them to the store for a replacement.

The five recalled products include a starter porridge, apple and banana oatmeal, and porridge for 1 to 3-year-olds. All batch and lot numbers and best-before dates were affected.