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The gene was found in 11 isolates from a Portuguese collection (n = 1,010; 58 serotypes; 2002–15) of clinical samples, foodstuff, food-animals and water. has been located on different plasmids (IncX4/IncHI2) in pig-associated multidrug-resistant, copper-tolerant 1,4,[5],12:i:-/ST34 and . Rissen/ST469 clones from human and pork products since at least 2011. Our data highlight dissemination of by successful resistant clones in Europe and raise questions about the efficacy of copper-based interventions to reduce colistin use.


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