Roan Pijnacker1, Timothy J Dallman2, Aloys S L Tijsma3, Gillian Hawkins4, Lesley Larkin2, Saara M Kotila5, Giusi Amore6, Ettore Amato7, Pamina M Suzuki8, Sarah Denayer9, Sofieke Klamer9, Judit Pászti10, Jacquelyn McCormick2, Hassan Hartman2, Gareth J Hughes2, Lin C T Brandal11, Derek Brown12, Joël Mossong13, Cecilia Jernberg14, Luise Müller15, Daniel Palm5, Ettore Severi5, Joannna Gołębiowska16, Blaženka Hunjak17, Slawomir Owczarek18, Simon Le Hello19, Patricia Garvey20, Kirsten Mooijman21, Ingrid H M Friesema22, Coen van der Weijden3, Menno van der Voort3, Valentina Rizzi6, Eelco Franz22. 1. National Institute for Public Health and the Environment (RIVM), Centre for Infectious Disease Control, Bilthoven, Netherlands. Electronic address: roan.pijnacker@rivm.nl. 2. Public Health England, London, UK. 3. Netherlands Food and Consumer Product Safety Authority (NVWA), Utrecht, Netherlands. 4. Health Protection Scotland, Glasgow, UK. 5. European Centre for Disease Prevention and Control, Solna, Sweden. 6. European Food Safety Authority, Parma, Italy. 7. Rapid Alert System for Food and Feed, Directorate-General for Health and Food Safety, European Commission, Brussels, Belgium. 8. Crisis Management in Food, Directorate-General for Health and Food Safety, European Commission, Brussels, Belgium. 9. National Institute for Public Health (Sciensano), Elsene, Belgium. 10. National Centre for Epidemiology, Budapest, Hungary. 11. Norwegian Institute of Public Health, Oslo, Norway. 12. Scottish Salmonella, Shigella, and Clostridium difficile Reference Laboratory, Glasgow, UK. 13. National Health Laboratory, Dudelange, Luxembourg. 14. Public Health Agency of Sweden, Solna, Sweden. 15. Statens Serum Institut, Copenhagen, Denmark. 16. Chief Veterinary Inspectorate, Warsaw, Poland. 17. Croatian Institute of Public Health, Zagreb, Croatia. 18. Istituto Superiore di Sanità, Rome, Italy. 19. Institut Pasteur, Paris, France. 20. Health Protection Surveillance Centre, Dublin, Ireland. 21. European Union Reference Laboratory for Salmonella, Bilthoven, Netherlands. 22. National Institute for Public Health and the Environment (RIVM), Centre for Infectious Disease Control, Bilthoven, Netherlands.
Abstract
BACKGROUND: Salmonella spp are a major cause of food-borne outbreaks in Europe. We investigated a large multi-country outbreak of Salmonella enterica serotype Enteritidis in the EU and European Economic Area (EEA). METHODS: A confirmed case was defined as a laboratory-confirmed infection with the outbreak strains of S Enteritidis based on whole-genome sequencing (WGS), occurring between May 1, 2015, and Oct 31, 2018. A probable case was defined as laboratory-confirmed infection with S Enteritidis with the multiple-locus variable-number tandem repeat analysis outbreak profile. Multi-country epidemiological, trace-back, trace-forward, and environmental investigations were done. We did a case-control study including confirmed and probable cases and controls randomly sampled from the population registry (frequency matched by age, sex, and postal code). Odds ratios (ORs) for exposure rates between cases and controls were calculated with unmatched univariable and multivariable logistic regression. FINDINGS: 18 EU and EEA countries reported 838 confirmed and 371 probable cases. 509 (42%) cases were reported in 2016, after which the number of cases steadily increased. The case-control study results showed that cases more often ate in food establishments than did controls (OR 3·4 [95% CI 1·6-7·3]), but no specific food item was identified. Recipe-based food trace-back investigations among cases who ate in food establishments identified eggs from Poland as the vehicle of infection in October, 2016. Phylogenetic analysis identified two strains of S Enteritidis in human cases that were subsequently identified in salmonella-positive eggs and primary production premises in Poland, confirming the source of the outbreak. After control measures were implemented, the number of cases decreased, but increased again in March, 2017, and the increase continued into 2018. INTERPRETATION: This outbreak highlights the public health value of multi-country sharing of epidemiological, trace-back, and microbiological data. The re-emergence of cases suggests that outbreak strains have continued to enter the food chain, although changes in strain population dynamics and fewer cases indicate that control measures had some effect. Routine use of WGS in salmonella surveillance and outbreak response promises to identify and stop outbreaks in the future. FUNDING: European Centre for Disease Prevention and Control; Directorate General for Health and Food Safety, European Commission; and National Public Health and Food Safety Institutes of the authors' countries (see Acknowledgments for full list).
BACKGROUND:Salmonella spp are a major cause of food-borne outbreaks in Europe. We investigated a large multi-country outbreak of Salmonella enterica serotype Enteritidis in the EU and European Economic Area (EEA). METHODS: A confirmed case was defined as a laboratory-confirmed infection with the outbreak strains of S Enteritidis based on whole-genome sequencing (WGS), occurring between May 1, 2015, and Oct 31, 2018. A probable case was defined as laboratory-confirmed infection with S Enteritidis with the multiple-locus variable-number tandem repeat analysis outbreak profile. Multi-country epidemiological, trace-back, trace-forward, and environmental investigations were done. We did a case-control study including confirmed and probable cases and controls randomly sampled from the population registry (frequency matched by age, sex, and postal code). Odds ratios (ORs) for exposure rates between cases and controls were calculated with unmatched univariable and multivariable logistic regression. FINDINGS: 18 EU and EEA countries reported 838 confirmed and 371 probable cases. 509 (42%) cases were reported in 2016, after which the number of cases steadily increased. The case-control study results showed that cases more often ate in food establishments than did controls (OR 3·4 [95% CI 1·6-7·3]), but no specific food item was identified. Recipe-based food trace-back investigations among cases who ate in food establishments identified eggs from Poland as the vehicle of infection in October, 2016. Phylogenetic analysis identified two strains of S Enteritidis in human cases that were subsequently identified in salmonella-positive eggs and primary production premises in Poland, confirming the source of the outbreak. After control measures were implemented, the number of cases decreased, but increased again in March, 2017, and the increase continued into 2018. INTERPRETATION: This outbreak highlights the public health value of multi-country sharing of epidemiological, trace-back, and microbiological data. The re-emergence of cases suggests that outbreak strains have continued to enter the food chain, although changes in strain population dynamics and fewer cases indicate that control measures had some effect. Routine use of WGS in salmonella surveillance and outbreak response promises to identify and stop outbreaks in the future. FUNDING: European Centre for Disease Prevention and Control; Directorate General for Health and Food Safety, European Commission; and National Public Health and Food Safety Institutes of the authors' countries (see Acknowledgments for full list).
Authors: Andréa K Mascitti; Diéssy Kipper; Rafael O Dos Reis; Juliana S da Silva; André S K Fonseca; Nilo Ikuta; Eduardo C Tondo; Vagner R Lunge Journal: Braz J Microbiol Date: 2021-05-14 Impact factor: 2.476
Authors: Florence E Buytaers; Assia Saltykova; Wesley Mattheus; Bavo Verhaegen; Nancy H C Roosens; Kevin Vanneste; Valeska Laisnez; Naïma Hammami; Brigitte Pochet; Vera Cantaert; Kathleen Marchal; Sarah Denayer; Sigrid C J De Keersmaecker Journal: Microb Genom Date: 2021-04
Authors: Claudia E Coipan; Timothy J Dallman; Derek Brown; Hassan Hartman; Menno van der Voort; Redmar R van den Berg; Daniel Palm; Saara Kotila; Tom van Wijk; Eelco Franz Journal: Microb Genom Date: 2020-02-26