Research contributing to the quantification of the human risk of antimicrobial resistance transfer via commensals present on food

Main research question/goal

To what extent are commensal E. coli (present in the primary animal production in Belgium) resistant to antimicrobials which are critical for public health? Which dose of these resistant bacteria may lead to colonization of the human gastro-intestinal tract and/or transfer of resistance genes to the endogenous microbiota? Which factors play a role? This research project aims to address these research questions. The animal production is an important reservoir of antimicrobial resistance genes and it is a potential vector for transfer of resistance genes to humans. This project will contribute to the quantification of the effect of human exposure to commensal resistant E. coli transferred via food.

 

Research approach

We characterize commensal E. coli strains isolated in the framework of the FAVV monitoring program that show resistances to quinolones and 3th/4th generation cephalosporins, for their capacity for resistance transfer. We study the survival in conditions present in the human gastro-intestinal system. In this way we can estimate the percentage of resistant strains that are at risk for transfer of resistance genes in the human intestine. By means of in vitro experiments, using the simulator of the human intestinal microbial ecosystem (‘SHIME’)  we quantify resistance selection and transfer of resistance genes. With this model we also study the effect of nutrient-related factors and exposure to antimicrobial substances.

 

Relevance/Valorisation

The majority of the studied commensal E. coli strains isolated from the primary animal production in Belgium and resistant to antimicrobials which are critical for human health, is able to easily transfer their resistance genes to other bacteria. By means of the SHIME simulating the human gut ecosystem we showed that transfer of resistance genes to the intestinal microbiota may occur fast, even without selection pressure (i.e. use of antibiotics) and irrespective of the meal size. The results of this project are spread via posters and lectures on (inter)national symposia and published in scientific journals. The developed model to study transfer of antibiotic resistance genes in the SHIME will be used in the frame of the postdoctoral mandate of Ellen Lambrecht to identify by epicPCR the taxonomic groups involved in antibiotic resistance transfer.

 

External partner(s)
Ugent - Fac. Bio-ingenieurswetenschappen