Emergence of Mobile Colistin Resistance (mcr-8) in a Highly Successful Klebsiella pneumoniae Sequence Type 15 Clone from Clinical Infections in Bangladesh

There is a marked paucity in our understanding of the epidemiology of colistin-resistant bacterial pathogens in South Asia. A report by Davies and Walsh (Lancet Infect Dis 18:256–257, https://doi.org/10.1016/S1473-3099(18)30072-0, 2018) suggests the export of colistin from China to India, Vietnam, and South Korea in 2016 was approximately 1,000 tons and mainly used as a poultry feed additive. A few reports forecast that the prevalence of mcr in humans and livestock will increase in South Asia. Given the high prevalence of blaCTX-M-15 and blaNDM in India, Bangladesh, and Pakistan, colistin has become the invariable option for the management of serious infections, leading to the emergence of mcr-like mechanisms in South Asia. Systematic scrutiny of the prevalence and transmission of mcr variants in South Asia is vital to understanding the drivers of mcr genes and to initiate interventions to overcome colistin resistance.