Laisnez Valeska, Vusirikala Amoolya, Nielsen Charlotte Salgaard, Cantaert Vera, Delbrassinne Laurence, Mattheus Wesley, Verhaegen Bavo, Delamare Hugues, Jourdan-Da Silva Nathalie, Lachmann Raskit, Simon Sandra, Cormican Martin, Garvey Patricia, McKeown Paul, Stephan Roger, Brown Derek, Browning Lynda, Hoban Ann, Larkin Lesley, Pardos de la Gandara Maria, Jernberg Cecilia, Takkinen Johanna, Balasegaram Sooria, Van Cauteren Dieter
Department of Epidemiology and Public Health, Sciensano, Brussels, Belgium.
ECDC Fellowship Programme, Field Epidemiology path (EPIET), European Centre for Disease Prevention and Control (ECDC), Stockholm, Sweden.
BMC Infect Dis. 2025 Feb 20;25(1):242. doi: 10.1186/s12879-025-10629-8.
In February 2022, the United Kingdom (UK) detected a cluster of monophasic Salmonella Typhimurium based on whole genome sequencing (WGS). Subsequently, several countries reported cases belonging to this cluster. Epidemiological, microbiological and traceability investigations pointed toward a chocolate food business operator (FBO) in Belgium. We describe the magnitude of the outbreak, investigations performed and control measures taken.
Cases were ascertained based on internationally agreed case definitions and interviewed about food consumption prior to disease onset. Analytical epidemiological studies were conducted by the UK and Ireland. The Belgian food safety authority (FSA) coordinated microbiological and traceability investigations.
A total of 456 cases (61% female), belonging to two genetically different WGS clusters, in 14 countries of the European Union, the UK, Switzerland, Canada and the United States were linked to the outbreak, between December 2021 and June 2022. 87% of cases were younger than 10 years. Brand A chocolate eggs, marketed for children, were reported as consumed by 168 cases (80%) with information. Analytical studies in the UK and Ireland showed a significantly higher odds of disease associated with consumption of brand A chocolate products. Retrospective investigations by the FSA revealed that routine samples (raw materials, intermediate, semi-finished and finished products as well as environmental and rinse oil samples) taken by the FBO linked to the Brand A products between December 2021 and January 2022 had tested positive for salmonella. Nine isolates were submitted to EnteroBase and matched with human isolates from both WGS clusters. The authorization for production was temporarily withdrawn on 8 April 2022 and all products of brand A were recalled worldwide, followed by a decrease in cases.
A multi-country salmonellosis outbreak linked to chocolate occurred in the months before Easter 2022. International collaboration between stakeholders from epidemiological, microbiological and food safety entities with rapid sharing of WGS results from human and nonhuman isolates were key in containing the outbreak. Implementation of routine WGS on human and nonhuman isolates will strengthen public health responses to future outbreaks. The magnitude of the outbreak underlines the importance of timely and open communication of FBOs to FSAs in case of salmonella detection.
2022年2月，英国基于全基因组测序（WGS）检测到一群单相鼠伤寒沙门氏菌。随后，多个国家报告了属于该群集的病例。流行病学、微生物学和可追溯性调查指向比利时的一家巧克力食品企业经营者（FBO）。我们描述了此次疫情的规模、开展的调查以及采取的控制措施。
根据国际商定的病例定义确定病例，并就发病前的食物消费情况进行访谈。英国和爱尔兰开展了分析性流行病学研究。比利时食品安全局（FSA）协调了微生物学和可追溯性调查。
在2021年12月至2022年6月期间，欧盟、英国、瑞士、加拿大和美国的14个国家共有456例病例（61%为女性）与此次疫情有关，这些病例属于两个基因不同的WGS群集。87%的病例年龄小于10岁。有168例（80%）有信息的病例报告食用了面向儿童销售的A品牌巧克力蛋。英国和爱尔兰的分析研究表明，食用A品牌巧克力产品与患病几率显著更高有关。FSA的回顾性调查显示，与A品牌产品相关的FBO在2021年12月至2022年1月期间采集的常规样本（原材料、中间产品、半成品和成品以及环境和冲洗油样本）沙门氏菌检测呈阳性。9株分离株被提交至EnteroBase，并与两个WGS群集中的人类分离株匹配。2022年4月8日，生产授权被暂时撤回，A品牌的所有产品在全球范围内被召回，随后病例数有所下降。
2022年复活节前几个月发生了一起与巧克力有关的多国沙门氏菌病疫情。流行病学、微生物学和食品安全实体的利益相关者之间的国际合作以及人类和非人类分离株WGS结果的快速共享是控制疫情的关键。对人类和非人类分离株实施常规WGS将加强对未来疫情的公共卫生应对。此次疫情的规模凸显了FBO在检测到沙门氏菌时及时、公开地与FSA沟通的重要性。
