Celia Manaia research interests include the study of the diversity and ecology of bacteria in human-impacted areas, with special emphasis on the potential impacts of antibiotic resistant bacteria and genes as environmental contaminants. The importance of municipal and hospital wastewater, the influence of the treatment processes, as well the tracing of possible antibiotic resistant bacteria and antibiotic resistance genes have been main research issues. The international and inter-laboratory antibiotic resistance monitoring in water environments, aiming at the development of surveillance schemes has also been an issue of interest.