Molecular epidemiology of NDM type carbapenemase-producing Escherichia coli from animals, food and human

Abstract

New Delhi metallo-β-lactamase (NDM) is one of the most clinically important carbapenemease genes, first identified in 2008 in a Swedish patient with a history of travel to India. The rapid dissemination and evolution of NDM constitutes a major public health concern regarding bacterial infection control and treatment. The hydrolytic activities of NDM variants contributed to its efficacy in conferring resistance to most β-lactam antibiotics, creating a worrisome situation in which therapeutic options are limited due to the ineffectiveness of broad-spectrum, last-resort carbapenem. NDM-producing E. coli has been reported in animals, food, human and environmental samples worldwide. However, the information is fragmented. In this study, we discussed the results of our comprehensive investigation of the prevalence of NDM-producing E. coli in animal, food, and human samples in Hong Kong. We utilized a total of 102 samples of NDM-producing E. coli: 35 from animal faeces, 28 from food (meat), and 39 from human stool. Our wide-scope study examined NDM-producing E. coli in Hong Kong. Firstly, we discovered that the substitution of NDM determinants was observed in this study: NDM-5 (n = 94) was found to be the predominant variant, followed by NDM-1 (n = 8). Secondly, blaNDM was confirmed to be carried in three major plasmids types, including IncX3 (n = 58), F1:A1:B49 (n = 20), and F2:A-:B (n = 13). Thirdly, two clonal lineages ST410 (n = 22) and ST69 (n = 12) were primarily identified. Both related to specific phylogroups (groups C and D) and pathotypes (UPEC and ExPEC). Our study sheds light on the surveillance of carbapenemase-producing producers in Hong Kong.