Dogs are carriers of Clostridioides difficile lineages associated with human community-acquired infections. (February 2021)

• Record Type: Journal Article
• Authors: Bjöersdorff, Olivia Graaf; Lindberg, Sanna; Kiil, Kristoffer; Persson, Søren; Guardabassi, Luca; Damborg, Peter
• Is Part Of: Anaerobe. Volume 67(2021)
• Publication Date: 2021-02
• Subjects: Clostridioides difficile -- Dog -- Environment -- Zoonosis -- Whole-genome sequencing -- Core genome MLST -- Antimicrobial susceptibility testing; Anaerobic infections -- Periodicals; Anaerobic bacteria -- Periodicals; Bacterial diseases -- Periodicals; Computer network resources; Anaerobic protozoa -- Periodicals; 579.3
• DOI: 10.1016/j.anaerobe.2020.102317
• Languages: English
• ISSNs: 1075-9964

Abstract

Abstract: There is an increasing concern about the role of animals as reservoirs of Clostridioides difficile . In this study, we investigated prevalence, antimicrobial resistance and zoonotic potential of C. difficile in dogs. Two-hundred and twenty-five dog faecal deposits were collected from trashcans in nine public gardens. C. difficile was isolated using selective plating and enrichment culture, identified by MALDI-TOF, tested for susceptibility to seven antibiotics by E-test, and sequenced on an Illumina NextSeq platform. Genome sequences were analysed to determine multilocus sequence types and resistance and toxin gene profiles. Zoonotic potential was assessed by measuring genetic variations of core genome (cg)MLST types between canine isolates and 216 temporally and spatially related human clinical isolates from a national database. C. difficile was isolated from 11 samples (4.9%). Seven isolates were toxigenic ( tcdA +, tcdB +, cdtA/B- ) and belonged to the sequence types ST2, ST6, ST10 and ST42. The four non-toxigenic isolates were assigned to ST15, ST26 and one novel ST. ST2, corresponding to PCR ribotype RT014/020, was the dominating lineage (n = 4) and, together with ST26 and ST42 isolates, showed close resemblance to human isolates, i.e. 2-5 allelic differences among the 1999 genes analysed by cgMLST. Three non-toxigenic isolates displayed resistance to clindamycin, erythromycin and tetracycline mediated by erm(B) and tet(M) . Resistance to metronidazole, moxifloxacine, rifampicin or vancomycin was not detected. In conclusion, a small proportion of faecal deposits contained toxigenic C. difficile such as ST2 (RT014/020), which is a major cause of community-acquired infections. Our finding suggests that pathogenic strains can be exchanged between dogs and humans. Highlights: C. difficile prevalence in 225 dog faecal deposits from 9 public gardens was 4.9%. The community-associated ST2 (RT014/20) lineage was most commonly detected. Based on sequencing, most isolates were closely related to local human CDI isolates. Resistance to metronidazole and vancomycin was not detected in canine C. difficile .