Public Health England (PHE) reported a cluster of 115 cases of S. Agona with isolates closely related by whole genome sequencing (WGS)-based analysis.
The majority of cases had sampling dates in 2018 (53) and 2017 (37) but the earliest was reported in April 2014.
A total of 19 S. Agona cases between 2015 and 2018 have isolates closely related to the UK WGS cluster. They have been reported by Denmark (two), Finland (16) and Ireland (one).
However, the Irish patient had travel history to the UK in the days prior to onset of disease.
Outbreak ongoing since 2014
The European Centre for Disease Prevention and Control (ECDC) said this means a multi-country outbreak has been ongoing since 2014 affecting 134 cases in four EU Member States.
The agency added detection of confirmed cases in several countries indicates the vehicle of infection is possibly distributed to different countries.
“The distribution of confirmed cases over different years indicates a continuous common source outbreak. The seasonal peak in notifications in April and May might indicate that the vehicle of infection is distributed mostly in these months.”
More than 60% of all cases are female with the median age of the 129 cases with available information being 39 years.
Sweden noted an increase of cases in 2017 compared to previous years but investigation did not identify a common suspected vehicle of infection. In 2018, four domestic cases have been reported.
Belgium, Germany and Spain have no increase in notifications this year.
Estonia, Greece, Luxembourg, Norway and Slovenia reported no isolates closely related to the outbreak strain or no S. Agona notifications at all in 2018.
S. Agona is the tenth most common Salmonella serotype in the European Union (EU). In 2012-2016, it was reported by 26 EU/EEA countries with 400-581 cases annually.
ECDC’s Food and Waterborne Disease team confirmed to us there is no connection with the S. Agona outbreak linked to Lactalis infant formula that sickened 38 infants in France, two from Spain and one in Greece last year.
Production to resume at Craon
Meanwhile, French authorities agreed last week to a gradual resumption of production at the Craon site of Lactalis following suspension as part of the outbreak investigation in December 2017.
A control plan has been validated by ANSES (L'Agence nationale de sécurité sanitaire de l'alimentation, de l'environnement et du travail) and official testing of products and in the environment will be carried out.
To start with, all products can only be marketed after enhanced controls and permission from authorities. Production of infant milk powder remains suspended.
Foodwatch condemned the ‘rush’ to resume production at the plant, especially as an inquiry into the incident is ongoing.
Emmanuel Besnier, Lactalis CEO, told French radio station RTL that the aim is to restart infant formula production this summer.
Ingrid Kragl, from the consumer organisation, voiced concerns about checks by Lactalis as part of the reinforced plans announced by authorities.
“Plans strengthened compared to what? We do not know anything for now of the checks led by Lactalis during all the years when Salmonella was present in the factory.”
The S. Agona strain that caused contamination in 2017 was the same as the one that led to 141 illnesses in 2005 when the Craon site was owned by Célia.