The aim of this study was to determine the occurrences of the group A rotavirus (RVA), norovirus (NoV) and human
adenovirus (HAdV) in the surface waters of an urban lagoon (Rodrigo de Freitas Lagoon) in the city of Rio de Janeiro,
Brazil. During one year of surveillance, water samples were obtained from the lagoon and other interconnected
ecosystems (river and beach). The samples were concentrated using an adsorption-elution method with a negatively
charged membrane and tested by qualitative and quantitative polymerase chain reaction assays. RVA was the most
prevalent virus detected (24.3%) with a viral load ranging from 3.0 x 10
1-5.6 x 10
4 genome copies/L, followed by NoV
(18.8%) and HAdV (16.7%). Considering water samples suitable for bathing, according to
Escherichia coli
criterion
(< 2,000 most probable number/100 mL), viruses were detected in 50% (57/114) of them. Physicochemical parameters
were also measured and showed possible correlations between turbidity and RVA presence and between pH and NoV
presence. These data demonstrate the importance of considering viral parameters to ensure water quality and the
utilisation of these parameters as additional tools for the characterisation of environmental contamination.
