Investigation of Two Outbreaks of Gastroenteritis in Tržič in September 2011 / Preiskava Dveh Izbruhov Gastroenteritisa V Tržiču V Septembru 2011

Uvod. Izbruh gastroenteritisa neopredeljene etiologije in izbruh salmoneloze sta bila hkrati v Tržiču septembra 2011. Namen preiskave izbruhov je bil odkriti izvor in poti prenosa okužbe s ciljem, da se sprejmejo ukrepi za prekinitev širjenja. Metode. V dveh retrospektivnih študijah primerov in kontrol je bila z univariatnimi in multivariatnimi analizami testirana povezava med gastroenteritisom neopredeljene etiologije oziroma salmonelozo in uživanjem hrane v gostilni ali pitjem vodovodne vode. Primer v prvi študiji je bil oboleli s salmonelozo, primer v drugi študiji pa je bil vsak občan z drisko in/ali bruhanjem. Primere obolelih so prijavili zdravniki; kontrole so bile izbrane med zdravimi osebami, ki so vrnile izpolnjeni vprašalnik. Rezultati. Osebe, izpostavljene hrani v gostilni, so imele 24,8-krat višje obete za obolevanje za salmonelozo kot neizpostavljeni (univariatna analiza RO 24,8; 95 % IZ 7,5-82,3; p < 0,05; multivariatna analiza RO 14,7; 95% IZ 3,5-61,3, p < 0,05). Občani, ki so pili vodo iz določenega vodnega vira, so imeli 3,4-krat višje obete, da so oboleli za gastroenteritisom neopredeljene etiologije kot neizpostavljeni (univariatna analiza RO 3,4; 95 % IZ je 2,2-5,1; p < 0,05; multivariatni analizi RO 2,9; 95 % IZ 1,7-5,3; p < 0,05). Statistično značilna je bila tudi povezava med obolevanjem in količino popite pitne vode. Zaključki. Z analitičnima študijama primerov in kontrol smo potrdili vzročno povezanost med salmonelozo in prehranjevanjem v določeni gostilni ter povezanost med gastroenteritisom neopredeljene etiologije in pitjem vodovodne vode iz določenega vodnega vira. Mogoč je vnos Salmonelle enteritidis v gostilno prek vodovodne vod

Managing of the outbreak of staphylococcal food poisoning in primary school

Background: In October 2010 an outbreak of staphylococcal food poisoning occurred in an elementary school with a kindergarten in Gorenjska

An international outbreak of Salmonella enterica serotype Enteritidis linked to eggs from Poland: a microbiological and epidemiological study

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)

An international outbreak of Salmonella enterica serotype Enteritidis linked to eggs from Poland: a microbiological and epidemiological study

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)