An outbreak of carbapenem-resistant Acinetobacter baumannii producing OXA-23 carbapenemase in western China

Twenty-two non-repetitive carbapenem-resistant Acinetobacter baumannii isolates were obtained from Intensive Care Unit patients. All of the isolates carried blaOXA-23, blaOXA-66, a novel cephalosporinase-encoding gene (blaADC-25) and a class 1 integron with an aacC1–orfP–orfQ–aadA1a cassette array and had identical enterobacterial repetitive intergenic consensus (ERIC) profiles. ISAba1 was found upstream of blaOXA-23, but was not associated with blaOXA-66 or blaADC-25.