Iceland has reported a record high number of E. coli cases, driven by a large outbreak in 2024.
A total of 79 people were diagnosed with confirmed or probable Shiga toxin-producing E. coli (STEC) infection. Patients ranged in age from less than 1 to 84 years old and included 36 males and 43 females. In 2023, only 14 cases were noted.
According to the Directorate of Health, it is the highest number of cases in a single year since the start of monitoring. Most infections were part of a serious outbreak in a preschool in Reykjavík in October.
The E. coli O145 outbreak sickened 49 people. Twelve children were hospitalized, of which five were admitted to intensive care and two required specialized treatment due to renal failure.
An investigation revealed that the origin of STEC infection was in ground (minced) meat used in a meal served at the school. Testing of E. coli strains grown from meat and from fecal samples of infected individuals confirmed the same strain of E. coli was involved. Food preparation procedures at the preschool were inadequate in terms of handling the meat, cooking it, and storing the meals.
Salmonella and Listeria
In total, 69 people were diagnosed with Salmonella infections, compared to 56 in 2023. In 2024, patients were 28 men and 41 women aged 1 to 87. Of these, 38 were of domestic origin, 18 of foreign origin and in 13 this information was not known. The most common serotypes were Salmonella Typhimurium, Salmonella Montevideo, and Salmonella Enteritidis.
A Salmonella Typhimurium outbreak was discovered at the end of January 2024. It was initially thought to be limited to preschool children in Húsavík, but patients of different ages were later identified in several regions of the country. Over almost five months, 17 people aged from under 1 to 78 years were infected with the same type of Salmonella Typhimurium.
Salmonella was later found at a chicken farm in Iceland. Strains from humans and poultry were sequenced and found to be the same type. Officials said it was possible that the source of infection was chicken meat, but this has not been confirmed.
A cluster of Salmonella Montevideo was detected in North Iceland in December 2024. Most cases were linked to a hospital, but patients were also detected in Dalvík, Siglufjörður and Reykjavík, with no apparent connection to this hospital. A total of 17 cases were found. Patients ranged in age from less than1 to 87 years old. Information was obtained on the items consumed by those infected and samples were taken from various foods, but the source could not be found.
Seven people were infected with Listeria. Patients were five men and two women aged 68 to 83. All are believed to have fallen sick in Iceland. Six cases were recorded in the first three months of the year and one in September.
Whole genome sequencing revealed that four of the six cases from the beginning of the year were the same strain, but it was not possible to trace the source of infections to specific foods.
Data on other pathogens
Campylobacter infections caused 132 cases. Patients were 69 males and 63 females who ranged in age from under 1 to 80 years old. Approximately 56 percent of the infections were acquired abroad. This is down from 155 infections in 2023.
Six individuals were diagnosed with confirmed Shigella infection while 15 suspected cases were reported. The test used detects genetic material that is common to Shigella and Enteroinvasive E. coli (EIEC) but does not distinguish between the two pathogens. Differentiation of EIEC from Shigella is difficult and not performed in Iceland.
Of the six confirmed cases, three were women and three were men. Four had the subtype Shigella flexneri and two had Shigella sonnei.
Overall, 52 individuals were diagnosed with cryptosporidiosis, of which 10 were children aged 1 to 14 and 42 were adults aged 19 to 71. Nine hepatitis A cases were reported affecting seven children and two adults, aged 5 to 28.
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