Characterising the overlap of C. difficile genotypes in different reservoirs can improve our understanding of possible transmission routes of this pathogen. Most of the studies have focused on a comparison of the PCR ribotype 078 isolated from humans and animals. Here we describe for the first time a comparison of C. difficile genotypes isolated during longer time intervals from different sources including humans, animals and the non-hospital environment.
Altogether 786 isolates from time interval 2008-2010 were grouped into 90 PCR ribotypes and eleven of them were shared among all host types and the environment. Ribotypes that were most common in humans were also present in water and different animals (014/020, 002, 029). Interestingly, non-toxigenic isolates were very common in the environment (30.8%) in comparison to humans (6.5%) and animals (7.7%). A high degree of similarity was observed for human and animal isolates with PFGE. In human isolates resistance to erithromycin, clindamycin and moxifloxacin was detected, while all animal isolates were susceptible to all antibiotics tested.
Our results show that many other types in addition to PCR Ribotype 078 are shared between humans and animals and that the most prevalent genotypes in humans have the ability to survive also in the environment and several animal hosts. The genetic relatedness observed with PFGE suggests that transmission of given genotype from one reservoir to the other is likely to occur.