Shiga toxin-producing E. coli (STEC) and Listeria infections in Europe are at their highest levels since the start of EU-wide surveillance in 2007.

Data comes from two 2023 epidemiological reports issued recently by the European Centre for Disease Prevention and Control (ECDC), which cover the European unio and European Economic Area (EEA).

Disease severity is also showing an increasing trend for both STEC infections and listeriosis. While the number of hemolytic-uremic syndrome (HUS) cases stabilized to 522 in 2023 since the record high in 2022, monitoring highly pathogenic STEC variants remains critical to guide public health management, said ECDC. HUS is a serious condition causing progressive kidney failure. 

E. coli situation
In 2023, 10,901 confirmed STEC infections were reported across 30 EU/EEA countries, marking a 22 percent increase compared to 2022. The ECDC said the rise in cases can partly be attributed to laboratory diagnostic tests that are more sensitive than traditional methods.

Overall, 36 percent of 3,959 STEC cases were hospitalized and 32 people died.

The highest notification rates were in Denmark, Ireland, Liechtenstein, Malta, and Norway. Germany reported the most cases followed by Denmark. Among travel associated patients with a known destination, the highest proportion of cases went to Egypt and Turkey.

The six most frequently reported serogroups were O157, O26, O146, O103, O145, and O91.

Sixteen incidents were reported through ECDC’s EpiPulse platform. Seven genetically related multi-country E. coli clusters involved at least 11 countries, with almost 400 cases. In two clusters, the suspected vehicle of infection was raw milk cheese and in another there was a link to ready-to-eat salad/iceberg lettuce. Also, 68 foodborne outbreaks with 306 cases were reported to the European Food Safety Authority (EFSA).

Listeria concerns
A total of 2,993 confirmed listeriosis cases with more than 1,500 hospitalizations, and 340 deaths were reported in 2023. The ECDC said the increasing elderly population, along with changing dietary habits such as higher consumption of ready-to-eat foods, may be contributing to the upward trend.

Germany, France, and Spain had the most cases. The highest incidence rates were observed in Finland, Sweden, and Portugal.

Ten new multi-country clusters were identified during the year. Also, 282 isolates matched with multi-country clusters detected before 2023. Data includes 161 multi-country clusters, of which 64 had matching non-human isolates. The median cluster duration was 2.9 years but ranged from 1 day to 14.8 years.

A dozen listeriosis alerts were launched in EpiPulse by six EU/EEA countries, ECDC, and one other country. A probable source was reported for four incidents. Three were linked to ready-to eat fish products and the other to cooked black olives. Also, 21 foodborne outbreaks were reported to EFSA.