Molecular epidemiological investigation of multidrug-resistant Acinetobacter baumannii strains in four Mediterranean countries with a multilocus sequence typing scheme.

Thirty-five multidrug-resistant Acinetobacter baumannii strains, representative of 28 outbreaks involving 484 patients from 20 hospitals in Greece, Italy, Lebanon and Turkey from 1999 to 2009, were analysed by multilocus sequence typing. Sequence type (ST)2, ST1, ST25, ST78 and ST20 caused 12, four, three, three and two outbreaks involving 227, 93, 62, 62 and 31 patients, respectively. The genes bla(oxa-58), bla(oxa-23) and bla(oxa-72) were found in 27, two and one carbapenem-resistant strain, respectively. In conclusion, A. baumannii outbreaks were caused by the spread of a few strains.