Evidence of Sharing of Klebsiella pneumoniae Strains between Healthy Companion Animals and Cohabiting Humans.

This study aimed to characterize the fecal colonization and sharing of strains between companion animals and humans living in close contact. Fecal samples were collected from 50 healthy participants (24 humans, 18 dogs, and 8 cats) belonging to 18 households. Samples were plated onto MacConkey agar (MCK) plates with and without cefotaxime or meropenem supplementation. Up to five colonies per participant were compared by pulsed-field gel electrophoresis (PFGE) after XbaI restriction. strains with unique pulse types from each participant were characterized for antimicrobial susceptibility, virulence genes, and multilocus sequence type (MLST). Fecal pulse types were compared to those of clinical strains from animal and human patients with urinary tract infections ( = 104). colonization was detected in nonsupplemented MCK in around 38% of dogs ( = 7) and humans ( = 9). strains isolated from dogs belonged to sequence type 17 (ST17), ST188, ST252, ST281, ST423, ST1093, ST1241, ST3398, and ST3399. None of the strains were multidrug resistant or hypervirulent. Two households included multiple colonized participants. Notably, two colonized dogs within household 15 (H15) shared a strain each (ST252 and ST1241) with one coliving human. One dog from H16 shared one PFGE-undistinguishable ST17 strain with two humans from different households; however, the antimicrobial susceptibility phenotypes of these three strains differed. Two main virulence genotypes were detected, namely and These results highlight the potential role of dogs as a reservoir of to humans and vice versa. Furthermore, to our best knowledge, this is the first report of healthy humans and dogs sharing strains that were undistinguishable by PFGE/MLST.