Prevalence, genetic diversity, antibiotic resistance and biofilm formation of Acinetobacter baumannii isolated from urban environments

Abstract

Abstract Aim Acinetobacter baumannii is a well-known nosocomial pathogen that has been isolated from different clinical sources. This pathogen also causes community-acquired infections, with mortality rates as high as 64%. The exact natural habitat of this bacterium is still unknown. In this study, we investigated the prevalence of A. baumannii in diverse soil and high-touch surface samples collected from a university campus, malls, parks, hypermarkets and produce markets, roundabout playground slides and bank ATMs. Methods and Results All obtained isolates were characterized for their antibiotic susceptibility, biofilm formation capacities, and were typed by multi-locus sequence analysis. A total of 63 A. baumannii isolates were recovered, along with 46 Acinetobacter pittii and 8 Acinetobacter nosocomialis isolates. Sequence typing revealed that 25 A. baumannii isolates are novel strains. Toilets and sink washing basins were the most contaminated surfaces, accounting for almost 50% of the isolates. A number of A. baumannii (n = 10), A. pittii (n = 19) and A. nosocomialis (n = 5) isolates were recovered from handles of shopping carts and baskets. The majority of isolates were strong biofilm formers and 4 isolates exhibited a multi-drug resistant phenotype. Conclusions Our study is the first to highlight community restrooms and shopping carts as potential reservoirs for pathogenic Acinetobacter species. Further studies are required to identify the reasons associated with the occurrence of A. baumannii inside restrooms. Proper disinfection of community environmental surfaces and spreading awareness about the importance of hand hygiene may prevent the dissemination of pathogenic bacteria within the community. Significance and Impact of the study Serious gaps remain in our knowledge of how A. baumannii spreads to cause disease. This study will advance our understanding of how this pathogen spreads between healthcare and community environments. In addition, our findings will help healthcare decision-makers implement better measures to control and limit further transmission of A. baumannii.