Extrahuman Epidemiology of Acinetobacter baumannii in Lebanon

Abstract

ABSTRACTThe presence ofAcinetobacter baumanniioutside hospitals is still a controversial issue. The objective of our study was to explore the extrahospital epidemiology ofA. baumanniiin Lebanon. From February 2012 to October 2013, a total of 73 water samples, 51 soil samples, 37 raw cow milk samples, 50 cow meat samples, 7 raw cheese samples, and 379 animal samples were analyzed by cultural methods for the presence ofA. baumannii. Species identification was performed byrpoBgene sequencing. Antibiotic susceptibility was investigated, and theA. baumanniipopulation was studied by two genotyping approaches: multilocus sequence typing (MLST) andblaOXA-51sequence-based typing (SBT).A. baumanniiwas detected in 6.9% of water samples, 2.7% of milk samples, 8.0% of meat samples, 14.3% of cheese samples, and 7.7% of animal samples. All isolates showed a susceptible phenotype against most of the antibiotics tested and lacked carbapenemase-encoding genes, except one that harbored ablaOXA-143gene. MLST analysis revealed the presence of 36 sequence types (STs), among which 24 were novel STs reported for the first time in this study.blaOXA-51SBT showed the presence of 34 variants, among which 21 were novel and all were isolated from animal origins. Finally, 30 isolates had new partialrpoBsequences and were considered putative newAcinetobacterspecies. In conclusion, animals can be a potential reservoir forA. baumanniiand the dissemination of new emerging carbapenemases. The roles of the novel animal clones identified in community-acquired infections should be investigated.