An outbreak of Salmonella has affected more than 200 people in Europe, the United Kingdom, and the United States.

The Salmonella Virchow outbreak started in June 2017 and most cases have been linked to local restaurants serving kebab meat. At least one person in the United States had gotten sick. A female patient from California had a travel history to Paris in 2019 and needed hospital treatment. 

The European Centre for Disease Prevention and Control (ECDC) and European Food Safety Authority (EFSA) said the number of confirmed cases represents only a small proportion of all infections in Europe, partly due to the varying sequencing capacities of countries.

A total of 210 cases have been reported with 111 from France, 34 in the Netherlands, 32 in the UK, 26 in Germany, four in Ireland, two in Denmark, and one in the U.S. 

Kebab meat products containing contaminated chicken are the likely vehicles of infections, and the bacteria has been circulating in the EU poultry meat production chain in France, Germany, Ireland, and the Netherlands.

Among interviewed cases, 10 people were hospitalized in Germany, five in France, four in Ireland, and two in the UK. No deaths have been reported. Patients range in age from younger than 1 to 92 years old with the median age from 22 to 80 depending on the country.

Johanna Takkinen, ECDC principal expert on food- and waterborne diseases, said: “ECDC encourages countries to sequence Salmonella Virchow isolates from domestically acquired human infections and interview cases with Salmonella Virchow sequence type 16 infections. Investigations should be focused on the consumption of poultry meat and related products and be carried out in close collaboration with food safety authorities.”

New infections are likely in the EU affecting all age groups until further investigations identify the sources and points of contamination along the chicken meat production chain, said ECDC and EFSA.

Spike of infections in late 2022
In January 2023, France reported 52 cases of Salmonella Virchow infection between August and December 2022 to the European surveillance portal for infectious diseases, called EpiPulse. In the following weeks, Denmark, Germany, the Netherlands, the UK, and the US reported cases belonging to the same microbiological cluster. The French outbreak strain is genetically similar to a previous multi-country outbreak of Salmonella Virchow in the Netherlands in 2020, with chicken meat as the suspected vehicle of infection.

Data shows multi-country peaks at irregular intervals since 2017, with the highest peak in the final quarter of 2022. The latest cases were reported in France and the Netherlands in February 2023.

A French outbreak in 2022 was linked to local kebab restaurants in one region. Forty-two sick people were involved. In 2021, an outbreak caused by the same strain was associated with a kebab restaurant in a different region.

In France, a questionnaire found consumption of kebabs with chicken meat, in the days before the onset of symptoms, by 19 of 24 cases interviewed, and 14 cited the same kebab outlet in one region.

Five French restaurants had been supplied with kebab meat by different German suppliers and a Polish company. Some of the involved German firms received raw materials from Belgian, Italian, Dutch, and Polish businesses. The outbreak strain was also detected in French broiler farms.

A lack of information, such as batch numbers, meant the role of the producers of kebab products, their meat suppliers, and the possible involvement of other operators, as sources of infections could not be established or ruled out, said ECDC and EFSA.