The Netherlands recorded an increase in foodborne outbreaks in 2024 and also provided details of a salmonella outbreak affecting several countries.
Significant increases were observed for Salmonella Enteritidis, Shiga toxin-producing E. coli (STEC), hepatitis A virus, and norovirus. The rise in incidence of Salmonella Enteritidis reflects a higher prevalence in the laying hen sector, where contaminated eggs are a leading cause of infections in humans.
According to a report by the National Institute of Public Health and the Environment (RIVM), the number of reported foodborne outbreaks amounted to 1179 with 5388 patients. This is up from 912 outbreaks in 2023, but similar to 2022 levels.
In 31 outbreaks, the causative agent was identified, with norovirus the most frequently reported, followed by salmonella. The largest (717 cases) was a norovirus outbreak linked to a cafe serving drinks during King's Day. A sick employee unknowingly spread the virus while asymptomatic. The employee reported he was sick when symptoms appeared and the cafe sent him home.
Health care costs associated with the 14 selected pathogens are estimated at €566 million ($665 million). In 2023, this will amount to more than 553 million euros (650 million US dollars). The estimated costs caused by contaminated food are €192 million ($225 million). That's just shy of €193 million ($227 million) in 2023.
Part of an outbreak that spanned several countries
1,665 people fell ill with salmonellosis, compared to 1,516 in 2023. The highest number of infections was among children aged 1 to 4 years and people aged 15 to 35 years.
Nine salmonella outbreaks involved 192 patients. In at least five of them, patients were hospitalized, and one death was recorded. The largest event, with 79 cases, was a nationwide outbreak of Salmonella Enteritidis associated with eggs.
Outbreak investigations were conducted in six clusters. Three of them were caused by Salmonella Enteritidis, two of which are ongoing. The remaining three were caused by Salmonella Typhimurium or the monophasic variant and were associated with imported beef, steak tartare and dried sausage.
One was an international outbreak with more than 325 cases in Denmark, France, Germany, Ireland and the UK. The UK outbreak was part of a cluster that began in October 2020. Investigations in Denmark have pointed to meat from the UK as a likely source. English authorities have confirmed the link to the slaughterhouse, and Hilton Foods has linked the problem to one of its suppliers.
A total of 40 Dutch patients were enrolled: 18 men and 22 women with a mean age of 26 years. Dutch patients mainly consumed steak or carpaccio, whereas Danish and English patients mainly consumed minced meat.
E. coli, listeria and hepatitis A
The number of Shiga toxin-producing E. coli infections increased from 573 to 645. A total of 36 different O-types were detected, but O157, O26, O145 and O103 were the most frequently detected. A person over 65 years of age has died directly or indirectly due to an E. coli infection.
Eleven patients developed hemolytic uremic syndrome (HUS), including five children under 6 years of age, two adolescents, one person in their 30s, and three people over 75 years of age.
About a quarter of patients said they likely contracted the infection abroad. The most frequently mentioned countries were Egypt, Türkiye, Morocco and Indonesia.
There were 115 cases of listeria reported, up from 95 in 2023. Ten adults died directly or indirectly from the infection, and three infants were stillborn or died shortly after birth.
Whole genome sequencing identified 38 clusters. In 2024, three clusters from previous years grew, where pollution was associated with fish processing sites. A new cluster with one isolate in 2023 and three in 2024 was associated with a smoked eel firm.
The number of hepatitis A cases increased from 153 in 2023 to 238. In two clusters, food was the likely route of transmission. The first case in 2024 sickened 14 out of 24 people, and the source was frozen blueberries. The Wageningen Food Safety Study found HAV RNA in two open packages from the same patient. In the second, 10 people became ill; grapes were a possible source.
In 2024, 4735 patients with campylobacteriosis were registered and 32 clusters were identified with a range from 2 to 15 isolates. Local health authorities have reported only one outbreak involving two people infected in Thailand.
(To sign up for a free subscription to Safety News, Click here)
