Science at the service of public health: Enterotoxigenic Clostridium perfringens

Authors: Alexandra Caron, Dr. Marie-Lou Gaucher

University of Montreal

Article published in La Terre de chez nous on December 11, 2023: https://www.laterre.ca/chroniques/page-de-conseils/la-science-au-service-de-la-sante-publique-clostridium-perfringens-enterotoxinogene/

Despite the fact that the Public Health Agency of Canada reports that over 4 million Canadians are affected by foodborne illness each year, very few of them will go so far as to investigate the infectious agent responsible for their illness, or even the source of this exposure. Epidemiological investigations represent the central pillar of foodborne illness (FBI) investigation and it is these investigations that have made it possible to position the zoonotic bacteria Salmonella and Campylobacter as the leading causes of foodborne illness in this country.

Research conducted in recent years has also highlighted the main food reservoirs of these two pathogens, with poultry meat representing a major source. However, these studies aimed at facilitating the identification of sources remain virtually absent to date for enterotoxigenic Clostridium perfringens, the third player in this zoonotic bacterial trio causing the greatest number of TIAs. Why?

Unique characteristics of enterotoxigenic C. perfringens

Research has highlighted certain particularities of enterotoxigenic C. perfringens. Among other things, this zoonotic subpopulation represents only 1% of the overall population of C. perfringens, and is harmless to human health. In addition, in the laboratory, no approach currently allows for the selective isolation of enterotoxigenic C. perfringens from a specimen that would be used to document a case of TIA, for example. In the end, it’s almost like looking for a needle in a haystack!

Promising work to describe the reservoirs of enterotoxigenic C. perfringens

In light of its recent research work, the Chair of Research in Meat Safety (CRSV) of the Faculty of Veterinary Medicine, whose main mission is to support the animal and food industries, recently developed a laboratory approach based on steps of enrichment in selective medium, polymerase chain reaction (PCR), growth on selective medium and colony hybridization in order to better describe the food reservoirs of enterotoxigenic C. perfringens.

The results obtained showed that up to 25% of broiler carcasses leaving the slaughterhouse to be sold directly to the supermarket or processed were positive for the presence of the pathogen.

A closer look at the potential sources of entry of enterotoxigenic C. perfringens along the chicken meat production chain suggests that poultry may serve as an ecological niche for this zoonotic bacterium. It has been identified from breeding birds, the hatchery, the feed, the rearing farm, and transport crates. Ongoing genetic characterization analyses will document the parental relationship between the isolated enterotoxigenic C. perfringens strains in order to better trace their source.