Molecular Investigation of Klebsiella pneumoniae from Clinical Companion Animals in Beijing, China, 2017-2019.

This work is aimed to elucidate the prevalence and characteristics of antimicrobial resistance, virulence, and molecular typing in Klebsiella pneumoniae from clinical companion animals in Beijing, China. In total, 105 K. pneumoniae (2.0%) isolates were recovered from 5359 samples (dogs, n = 3356; cats, n = 2003). All tested isolates exhibited high resistance to amoxicillin-clavulanate (74.3%). Moreover, resistance rates in dog isolates (2.1%) were significantly higher than in cat isolates (0.9%); however, the rate of multidrug-resistance (MDR) was 57.1% and the MDR prevalence in cats was significantly higher than dogs. Whole-genome sequencing demonstrated plasmids IncX4 and IncFIA (HI1)/FII(K) carried mcr-1 (n = 1) and mcr-8 (n = 1), but blaOXA-181 (n = 1) and blaNDM-5 (n = 4) were harbored in IncX3-type plasmids, and the above genes were in different isolates. The most prevalent sequence types (STs) in companion animals were ST1 (n = 9) and ST37 (n = 9). Compared to National Center for Biotechnology Information (NCBI) data on human K. pneumoniae, resistance genes blaCTX-M and blaTEM were more prevalent in human isolates; however, aac(6')-Ib-cr and oqxAB showed a higher prevalence in companion animals. Hypermucoviscosity was reported in 9 (8.6%) isolates, whereas 64 isolates (61.0%) were hypervirulent K. pneumoniae (hvKP) via the Galleria mellonella. These findings validate the high risk of K. pneumonia and necessitate its relevant control in pet clinics.