Polymixins are a type of antibiotic of which Colistin is one. Polymixins and in particular colistin are one of our last lines of defense against serious bacterial infection. While resistance has been seen against these antibiotics it has only occurred through mutations in the chromosome of the bacteria making resistance difficult to pass on to other bacteria. A new research article in The Lancet Infectious Diseases has reported that, for the first time, resistance to colistin has been detected on a plasmid. This is of significance as bacteria can transfer/share plasmids readily and thus spread resistance much more quickly then through mutations in the chromosome.
This raises the real possibility of the emergence of untreatable diseases. Are we at the beginning of a new era of bacterial superiority?