Spatial molecular epidemiology of carbapenem‐resistant and New Delhi metallo beta‐lactamase (blaNDM)‐producing Escherichia coli in the piglets of organized farms in India

Aim A cross-sectional study was conducted in ten government organized pig farms between 2014 and 2016 representing seven states of India to understand the epidemiology of carbapenem resistance in Escherichia coli isolates. Methods and Results In this study, 673 fecal samples both from non- diarhhoeic (n=501) and diarrhoeic (n=172) piglets were processed for isolation of carbapenem resistant E. coli. Wherein, 112 confirmed E. coli isolates were further subjected for genotypic confirmation of carbapenem resistance and virulence factors. Of the 112 isolates, 23 were phenotypically resistant to carbapenem and 8 were carrying the New Delhi Metallo Beta-lactamase (blaNDM) gene. The carbapenem resistant isolates also produced Extended Spectrum Beta-lactamases (ESBL) and were multi drug resistant (MDR). The PCR based pathotyping revealed presence of stx1, stx2, eae and hlyA genes. The enterobacterial repetitive intergenic consensus (ERIC) PCR dendrogram analysis of the isolates yielded 3 distinct clusters. The statistical analysis revealed no association between carriages of carbapenem resistant E. coli in different breed of piglets however, location, sex, health status of piglets and different age groups showed significant difference. The spatial analysis with SaTScan helped in identification of carbapenem resistant clusters. Conclusions The presence of carbapenem resistant E. coli isolates with virulence genes in piglets may have a potential public health risk through their possible access and spread via the food chain and environment. Efflux pump may also play an important role in carbapenem resistance in piglet E. coli isolates. Furthermore, identification of risk factors in relation to spatial clusters may help in formulating a better preventive strategy for reducing the risk of spreading of carbapenem resistant bacteria. Significance and impact of the study 1. Piglets may be one of the important reservoirs of Carbapenem Resistant Enterobacteriaceae (CRE) and have great public health significance. 2. Apart from carbapenemase, efflux pump is also equally important for carbapenem resistance. 3. This appears to be the first report of blaNDM in piglets from India. This article is protected by copyright. All rights reserved.