Classification of pig farm compartments according to their role in the epidemiology of Clostridioides difficile (task 3.4)

In order to assess C. difficile/AMR dissemination between humans, animals and the environment, studies were conducted on samples from 4 countries (2 HOALs Portugal, Austria, 1 agricultural facility Estonia, single compartments Ireland). The results obtained allowed to perform a classification of pig farm compartments according to their role in the epidemiology of C. difficile, which was identified in all the following ecosystems: pig barn (faeces), manure (pig), wild animals, soil (agricultural fields), river water, ground water, wastewater treatment plant and air. In addition, in each HOAL, a different toxigenic C. difficile RT (RT033, RT078 and RT049, respectively) was dominant, reflecting well-established transmission chains and a resilient source. Overall, the results obtained from the 3 HOALs/agricultural facility showing the presence of dominant clones in compartments associated with the pig production unit suggest a transmission chain involving these animals. They contribute to unveiling the role played by animal and environmental reservoirs within the C. difficile epidemiology.