A first case of New Delhi metallo-β-lactamase-7 in an Escherichia coli ST648 isolate in Japan.

We report a first identification case of an Escherichia coli ST648 isolate producing a variant New Delhi metallo-β-lactamase (NDM) -7 in Japan, which was recovered from a patient hospitalized in India. Although the first isolate, NDM-1, was identified in Japan in 2010, NDM-producing bacteria have only been isolated from seven patients to date, and no other variant of NDM producing organism has been reported yet. The emergence of NDM variants in Enterobacteriaceae is of great concern, and the use of rigorous screening tests and preventive measures against infection is imperative.