| Autor: |
Torpdahl M; Statens Serum Institut, Copenhagen, Denmark., White ED; Statens Serum Institut, Copenhagen, Denmark., Schjørring S; Statens Serum Institut, Copenhagen, Denmark., Søby M; Danish Veterinary and Food Administration, Glostrup, Denmark., Engberg J; Department of Clinical Microbiology, Zealand University Hospital, Slagelse, Denmark., Engsbro AL; Department of Clinical Microbiology, Copenhagen University Hospital, Hvidovre, Denmark., Holt HM; Department of Clinical Microbiology, Odense University Hospital, Odense, Denmark., Lemming L; Department of Clinical Microbiology, Aarhus University Hospital, Aarhus, Denmark., Lützen L; Department of Clinical Microbiology, Lillebaelt Hospital, Vejle, Denmark., Olesen B; Department of Clinical Microbiology, Copenhagen University Hospital, Herlev and Gentofte, Denmark., Coia JE; Department of Clinical Diagnostics, Hospital South West Jutland, Esbjerg, Denmark., Kjelsø C; Statens Serum Institut, Copenhagen, Denmark., Müller L; Statens Serum Institut, Copenhagen, Denmark. |
| Abstrakt: |
Between November and December 2021, the first ever recorded outbreak of enteroinvasive Escherichia coli in Denmark occurred at national scale. We describe the investigation of this outbreak, which was initially recognised in early December 2021. A total of 88 cases (58 female; 30 male) with a median age of 52 years (range: 0-91) were detected by PCR-based diagnostic methods. Case ascertainment was complicated by current culture-free diagnostic procedures, with only 34 cases confirmed by culture, serotyping and whole genome sequencing. Isolates from cases grouped into two serotypes (O136:H7 and O96:H19), which was supported by whole-genome-sequence-phylogeny, also yielding two clusters. Interviews of 42 cases and traceback investigation pointed towards consumption of ready-to-eat salads as the outbreak cause. While the ready-to-eat salads comprised different vegetables, imported spring onions were the only common ingredient and thus the likely source. Environmental investigations failed to recover outbreak strains. This report highlights the value of fast typing (here O-typing) to confirm cases in an outbreak situation. Timely communication and data sharing are also important, and were facilitated by the national collaboration between relevant laboratories, the public health institute and the veterinary and food administration. High hygiene standards for imported fresh vegetables intended for ready-to-eat products are essential. |
