A new rapid risk assessment from the European Centre for Disease Prevention and Control (ECDC) shows that twenty-one cases of Listeria monocytogenes IVb sequence type ST 6 infections have been reported in the Netherlands (19 cases) and Belgium (two cases). This outbreak was identified using whole genome sequencing (WGS) analysis.
The patients involved had onset of illness between 2017 and August 2019. Three patients died and one suffered a miscarriage due to the infection. The close genetic relatedness of the strains, and the temporal distribution of the cases suggests a prolonged, intermittent, common source food-borne outbreak which occurred in at least two EU member states.
Nine isolates from six sliced ready-to-eat (RTE) meat products, produced between 2017 and 2019 by the Dutch manufacturing company A, were found to be contaminated with L. monocytogenes strains matching the outbreak strain.
Although the exact points of contamination have not yet been identified, the results of the investigation suggest that the contamination may have happened at the Dutch company, which was the only common manufacturing point of the contaminated products. The company distributed products to several EU countries as well as to countries outside the EU.
Company A stopped production in October 2019, and finalised the withdrawals and recalls of all RTE meat products. This measure lowered the risk of new cases occurring, which may be associated with this company’s products.
Pregnant women, the elderly and immunocompromised people are at higher risk of invasive listeriosis, which is associated with severe clinical course and potential death.
Specific attention should be paid to the administration of RTE meat products to people in hospitals, nursing homes and those belonging to vulnerable population groups.
Source: ECDC, 26 November 2019