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bioRxiv · 10.1101/467589

Evolutionary dynamics of carbapenem-resistant Acinetobacter baumannii circulating in Chilean hospitals

Opazo-Capurro, A.·San Martin, I.·Quezada-Aguiluz, M.·Morales, F.·Dominguez-Yevenes, M.·Lima, C.·Esposito, F.·Cerdeira, L. T.·Bello-Toledo, H. M.·Lincopan, N.·Gonzalez-Rocha, G. E.
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Abstract

We analyze the evolutionary dynamics of ninety carbapenem-resistant Acinetobacter baumannii (CRAB) isolates collected between 1990 and 2015 in Chile. CRAB were identified at first in an isolate collected in 2005, which harbored the ISAba1-blaOXA-69 arrangement. Later, OXA-58- and OXA-23-producing A. baumannii strains emerged in 2007 and 2009, respectively. This phenomenon was associated with variations in the epidemiology of OXA-type carbapenemases, linked to nosocomial lineages belonging to ST109 (CC1), ST162 (CC79), ST15 (CC15) and ST318 (CC15).

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Opazo-Capurro, A., San Martin, I., Quezada-Aguiluz, M., Morales, F., Dominguez-Yevenes, M., Lima, C., Esposito, F., Cerdeira, L. T., Bello-Toledo, H. M., Lincopan, N., Gonzalez-Rocha, G. E.. 2018-11-11. Evolutionary dynamics of carbapenem-resistant Acinetobacter baumannii circulating in Chilean hospitals. https://doi.org/10.1101/467589

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