Ornamental and recreational waters of easy access are quite attractive and can hide threats to human health. Here we evaluated, the microbiota of ornamental waters in a Lisbon park (1 year), as well as, the microbiota of two dams with nautical recreational activities and fluvial beach to assess the risk for human health. In the microbiota, we identified faecal indicator bacterium, E.coli, and other potential human pathogens such as A.baumannii, Aeromonas, E.cloacae, K.pneumoniae, Pseudomonas and Raoutella. The identification of known healthcare associated infections agents such as K. pneumoniae, as well as species of Pseudomonas (P.fluorescens, P.putida and P.oryzihabitans) that recently have been identified as etiological agents in immunosuppressed individuals is of particular relevance. The same bacterial species were isolated from biofilm
and water suggesting the existence of an equilibrium between planktonic and biofilm organized bacteria. The role played by biofilm assembly on the emergence of antibiotic resistance is still ongoing for the isolated bacteria, as well as the possible interaction between water chemical composition and bacteria isolates. Potential pathogens (biofilm or planktonic) represent a significant cause of acute bacterial infections mainly in specific populations (paediatric and geriatric). These results support periodic control of ornamental water microbiota as a preventive messure.N/
