Multidrug-resistant Proteus mirabilis isolates carrying bla(OXA-1) and bla(NDM-1) from wildlife in China: increasing public health risk

The emergence of multidrug resistance (MDR) in Proteus mirabilis clinical isolates is a growing public health concern and has serious implications for wildlife. What is the role of wildlife has been become one of the hot issues in disseminating antimicrobial resistance. Here, 54 P. mirabilis isolates from 12 different species were identified. Among them, 25 isolates were determined to be MDR by profile of antimicrobial susceptibility; 10 MDR P. mirabilis isolates were subjected to comparative genomic analysis by whole genome sequencing. Comprehensive analysis showed that chromosome of P. mirabilis isolates mainly carries multidrug-resistance complex elements harboring resistance to carbapenem genes bla(OXA-1), bla(NDM-1), and bla(TEM-1). Class I integron is the insertion hotspot of IS26; it can be inserted into type I integron at different sites, thus forming a variety of multiple drug resistance decision sites. At the same time, Tn21, Tn7, and SXT/R391 mobile elements cause widespread spread of these drug resistance genes. In conclusion, P. mirabilis isolates from wildlife showed higher resistance to commonly used clinic drugs comparing to those from human. Therefore, wild animals carrying MDR clinical isolates should be paid attention to by the public health.