Mcr-1, the gene that enables deadly bacteria to become resistant to even last resort antibiotics, such as colistin, has been identified in a Brazilian patient for the first time, according to research published in Antimicrobial Agents and Chemotherapy.
The gene was first isolated in China in late 2015, followed by cases in Denmark, Canada and eventually the U.S. The latest case in Brazil was identified in a 60-year-old patient with diabetes. The patient tested positive for a type of E. coli carrying the mcr-1 gene. After going through multiple courses of antibiotic treatment for a foot infection, which did not improve, the patient's foot was amputated, according to the paper.
The researchers used whole genome analysis to determine that cell structures within the the resistant E. coli are surprisingly similar to those found in other bacteria that have been found to carry mcr-1. This strongly suggests the parts of infectious bacteria that are able to self-replicate may be contributing to the spread of the resistant gene, the authors concluded.