The antibiotic Polymyxin E is used to prevent growth of Gram negative bacteria such as E.coli, and is one of a few remaining drugs that can be used to treat multidrug resistant bacteria; W.H.O. has categorized Polymyxin E as a last resort antibiotic.
E.coli resistance against Polymyxin E was mostly related to chromosomal mutations previously; this type of resistance is not transferred to other bacterial species and was not thought to be of particular concern.
MCR1 is transmissible polymyxin E-resistant gene that has been found in China, raising concerns that resistance may be transferred to other bacterial species which could lead to super resistant nightmare bacteria that would be resistant to every kind of antibiotic.
Drug resistant bacteria are known to spread through livestock and livestock products in developing countries. The researchers hypothesized large quantities of polymyxin E being added to animal feed in Vietnam may be driving the spread of resistance, and decided to test the prevalence of resistant bacteria in rural areas.
The prevalence of polymyxin E-resistant bacteria was found to be extremely high at 70.4% in rural areas, and the resistant bacteria carried the mcr1 gene helping the spread of resistance occur much faster than expected.
Yoshimasa Yamamoto says this nightmare bacteria could pose a significant threat in the treatment of infectious disease, the number of refractory infections for which antibiotics do not work will increase affecting clinical practice, making it necessary to strengthen international surveillance systems and promptly take preventative measures.
