The Salmonella and Listeria (SEL) unit carries out reference, surveillance and research activities focusing on these two major bacterial pathogens involved in foodborne human infections.

Reference activities

The unit performs reference activities on Listeria monocytogenes as part of its National (NRL) and European (EURL) Reference Laboratory mandates. It is the associate laboratory of the Salmonella NRL (Ploufragan-Plouzané-Niort Laboratory). The unit contributes to improving detection and typing tools and organises inter-laboratory proficiency tests (ILPTs) and training sessions for the implementation of methods under these mandates.

Surveillance activities

Data from the unit’s reference and research activities provide input for its surveillance work. The databases managed by the unit are regularly used in situations of alerts to help risk managers direct epidemiological investigations. The unit is involved in coordinating a network of almost 130 laboratories and participates in the design and implementation of computerised epidemiological tools contributing to the surveillance of Salmonella from farm to fork.

Expert appraisal activities

Some of the unit’s scientists are asked to participate in the expert committees of ANSES and the European Food Safety Authority (EFSA) or be involved in the work of standardisation bodies (AFNOR, CEN and ISO). Scientific and technical expertise is provided to the Directorate General for Food (DGAL) and the networks of partner laboratories that the unit coordinates. Moreover, the unit helps transfer knowledge to the public authorities and to agro-industrial technical institutes. Every year, numerous analyses are performed that include conventional and molecular serotyping and microbiological sequencing and analyses for the purposes of detection, characterisation and enumeration.

Research activities

The unit carries out research projects to characterise bacterial hazards in the food chain, in order to improve the control of food safety. This work focuses on several themes:

• the integration of genomic approaches for the characterisation of isolates;
• the structure of pathogenic bacterial populations in food;
• the development of more effective detection and typing methods;
• the detection of markers for the virulence, resistance and adaptation of pathogens in different environments;
• the implementation of source attribution studies.

Data from the unit’s reference and research activities provide input for its surveillance work. The databases managed by the unit are regularly used in situations of alerts to help risk managers direct epidemiological investigations. The unit is involved in coordinating a network of almost 130 laboratories and participates in the design and implementation of computerised epidemiological tools, thus contributing to the surveillance of non-human Salmonella from farm to fork.

The unit carries out its work in a cross-cutting manner with the laboratory and Agency's food safety units, departments and platforms. It establishes national and international partnerships for all its activities.