Cross-border outbreak of listeriosis caused by cold-smoked salmon, revealed by integrated surveillance and whole genome sequencing (WGS), Denmark and France, 2015 to 2017

Susanne Schjørring (1) , Sofie Gillesberg Lassen (1) , Tenna Jensen (2) , Alexandra Moura (3, 4) , Jette S. Kjeldgaard (5) , Luise Müller (1) , Stine Thielke (1) , Alexandre Leclercq (3, 4) , Mylène M Maury (3, 4) , Mathieu Tourdjman (6) , Marie-Pierre Donguy (7) , Marc Lecuit (8, 3, 4, 9, 10, 11) , Steen Ethelberg (1) , Eva Nielsen (1)

1 Statens Serum Institut [Copenhagen]
2 Danish Veterinary and Food Administration
3 CC-OMS / WHO-CC - Centre collaborateur de l'OMS Listeria / WHO Collaborating Centre Listeria
4 CNRL - Centre National de Référence Listeria - National Reference Center Listeria
5 DTU - Danmarks Tekniske Universitet = Technical University of Denmark
6 Santé publique France - French National Public Health Agency [Saint-Maurice, France]
7 DGAL - Direction Générale de l'Alimentation
8 Biologie des Infections - Biology of Infection
9 UPD5 - Université Paris Descartes - Paris 5
10 CHU Necker - Enfants Malades [AP-HP]
11 Imagine - U1163 - Imagine - Institut des maladies génétiques (IHU)

In August 2017, an outbreak of six listeriosis cases in Denmark was traced to cold-smoked salmon, using epidemiological investigations and whole-genome sequencing (WGS) analyses. Exchange of genome sequences allowed identification in France of a food isolate from a salmon-derived product and a human isolate from 2016 within the same cgMLST cluster as the Danish isolates (L2-SL8-ST8-CT771). The salmon product came from a third European Union country. WGS can rapidly link human cases and food isolates across Europe.

Keywords: Cross-border outbreak; WGS; cold-smoked salmon; food-borne infections; listeriosis; surveillance; whole genome sequencing

Domains: Life Sciences [q-bio]; Life Sciences [q-bio]; Human health and pathology; Life Sciences [q-bio]; Human health and pathology; Infectious diseases; Life Sciences [q-bio]; Microbiology and Parasitology; Life Sciences [q-bio]; Microbiology and Parasitology; Bacteriology

Susanne Schjørring, Sofie Gillesberg Lassen, Tenna Jensen, Alexandra Moura, Jette S. Kjeldgaard, et al.. Cross-border outbreak of listeriosis caused by cold-smoked salmon, revealed by integrated surveillance and whole genome sequencing (WGS), Denmark and France, 2015 to 2017. Eurosurveillance, 2017, 22 (50), ⟨10.2807/1560-7917.ES.2017.22.50.17-00762⟩. ⟨pasteur-02183799⟩