Global impact of -positive bacteria on "one health".

Polymyxins, especially polymyxin B and polymyxin E (colistin), are considered to be the last line of defence against infections caused by multi-drug-resistant (MDR) gram-negative bacteria such as carbapenem-resistant (CRE). However, the recent emergence and dissemination of the plasmid-mediated colistin resistance gene and its variants pose a serious challenge to public health and the livestock industry. This review describes the prevalence and dissemination of -positive isolates from different sources, including animals (food animals, pet animals and wildlife), humans (healthy populations and patients) and the environment (farms, urban and rural communities and natural environments) based on existing epidemiological studies of and MCR-1-producing bacteria around the world. The major mechanisms of transmission across humans, animals and the environment are discussed.