Abstract Title
Virological analyses in collective catering outbreaks in France between 2018 and 2024
Presenter
Catherine HENNECHART-COLLETTE, Anses, Laboratory for food safety, Maisons-Alfort, France
Co-Author(s)
Catherine Hennechart-Collette, Lisa Fourniol, Audrey Fraisse, Sylvie Perelle - Anses, Laboratory for food safety, Maisons-Alfort, France
Abstract Category
Food & Environmental Virology-I (Food)
Abstract
Enteric viruses are a significant cause of foodborne illnesses, presenting symptoms such as vomiting, diarrhea, abdominal pain, and fever. Among these, human noroviruses (NoV) are the main viruses suspected of causing foodborne outbreaks and represent a serious public health concern.
This study assessed the presence of norovirus genogroup I (NoV GI) and norovirus genogroup II (NoV GII) in various foodstuffs during 61 foodborne outbreak investigations in France (2018–2024). A total of 408 suspect food samples were analyzed for the presence of NoV GI and GII using methods compliant with ISO 15216 or in-house protocols. The analysis included the implementation of process controls (MNV-1) and amplification controls, as required by ISO 15216 standards.
NoV was detected in nine food samples: four with NoV GI and five with NoV GII. For three samples linked to a single outbreak, NoV GII.17 was identified. Viral genomic levels in NoV-positive samples ranged from 2.59E+01 to 5.52E+04 genome copies per gram. MNV-1, the process control virus, was found at > 1% in 285/408 RNA extracts, with recoveries ranging from 2.9% to 70.2%. NoV inhibition rates in RNA extracts were less than 75%, with mean inhibition rates of 0–17.4% for NoV GI and 0–15.6% for NoV GII.
These results highlight the importance of adhering to ISO 15216 standards, particularly the use of process controls and amplification controls, to ensure accurate detection of enteric viruses. This approach improves the reliability of epidemiological investigations, allowing better tracing of foodborne contamination sources and linking them to clinical cases.
This study assessed the presence of norovirus genogroup I (NoV GI) and norovirus genogroup II (NoV GII) in various foodstuffs during 61 foodborne outbreak investigations in France (2018–2024). A total of 408 suspect food samples were analyzed for the presence of NoV GI and GII using methods compliant with ISO 15216 or in-house protocols. The analysis included the implementation of process controls (MNV-1) and amplification controls, as required by ISO 15216 standards.
NoV was detected in nine food samples: four with NoV GI and five with NoV GII. For three samples linked to a single outbreak, NoV GII.17 was identified. Viral genomic levels in NoV-positive samples ranged from 2.59E+01 to 5.52E+04 genome copies per gram. MNV-1, the process control virus, was found at > 1% in 285/408 RNA extracts, with recoveries ranging from 2.9% to 70.2%. NoV inhibition rates in RNA extracts were less than 75%, with mean inhibition rates of 0–17.4% for NoV GI and 0–15.6% for NoV GII.
These results highlight the importance of adhering to ISO 15216 standards, particularly the use of process controls and amplification controls, to ensure accurate detection of enteric viruses. This approach improves the reliability of epidemiological investigations, allowing better tracing of foodborne contamination sources and linking them to clinical cases.