The Initial Event

On October 22, the Chief Epidemiologist received a report of a confirmed STEC infection in a preschool-aged child treated at Landspítali’s emergency department. Other children from the same preschool had sought medical attention for gastrointestinal symptoms, raising concerns about a potential outbreak. That evening, a steering group was convened following established guidelines for investigating foodborne illness outbreaks. As a precaution, the preschool operator temporarily closed the facility.

Findings: Source and Impact of the Outbreak

The outbreak affected 49 individuals, including 45 children attending Mánagarður Preschool in Reykjavík and four individuals connected to the preschool. Twelve children were hospitalized at Landspítali’s pediatric ward, with five admitted to the intensive care unit. Two of these children required dialysis due to kidney failure.

The investigation identified minced meat used in a meal served at the preschool on October 17 as the source of the infections. Microbiological tests confirmed the presence of the same E. coli strain (E. coli O145:H25) in both the minced meat and stool samples of affected individuals. Meal preparation practices at the preschool, including handling, cooking, and storage of the minced meat meal, were found to be inadequate.

Preschool Reopening

Following the outbreak, the Reykjavík Health Authority conducted a thorough inspection of practices at the preschool and the facility, implemented improved food safety protocols, and provided staff guidance. The facility underwent extensive cleaning and disinfection and resumed operations on November 5.

Guidelines were issued by the Chief Epidemiologist to determine when children could safely return. To minimize risks, the preschool temporarily transitioned to purchased meals, with further decisions to be made in consultation with Health Authority.

STEC Infections

STEC is a strain of E. coli bacteria that produces harmful toxins, causing the range of gastrointestinal symptoms. The bacteria are zoonotic, meaning they can transfer between animals and humans, often through contaminated food or water. While undercooked beef and unpasteurized milk are common sources, other foods have also been implicated in past outbreaks.

STEC symptoms are mainly diarrhea, ranging from mild to bloody diarrhea; abdominal pain and vomiting can also occur. STEC can lead to severe complications like hemolytic uremic syndrome (HUS), particularly in children.

The Chief Epidemiologist

• Final Report: Steering Group Investigation into Shiga-Toxin Producing E. coli (STEC) Outbreak (Icelandic). Published December 2024