Extensively and multi drug-resistant Acinetobacter baumannii recovered from technosol at a dump site in Croatia

In a karst pit above City of Rijeka in Croatia the hazardous industrial waste was continuously disposed from 1955 to 1990, and later it was periodically used as an illegal dump site. The surface part of a technosol at the edge of dump was analysed mineralogically, geochemically and bacteriologically. From the technosol rich in petroleum hydrocarbons and heavy metals three isolates of Acinetobacter baumannii were recovered. Isolates from technosol shared many features that are previously described for clinically isolates: the affiliation to IC1 and 2, multi-drug resistant (MDR) or extensively drug-resistant (XDR) antibiotic resistance profile, carbapenem resistance mediated by bla_OXA72 and bla_OXA23 genes, and the expression of virulence factors. In in vitro conditions, isolates were able to survive in contact with technosol during 58days of monitoring. The most probable source of A. baumannii in technosol was the illegally disposed hospital waste. Proper management and disposal of human solid waste is mandatory to prevent the spread of clinically important A. baumannii in nature.