Detection and quantification of human adenoviruses in surface waters by nested PCR, TaqMan real-time PCR and cell culture assays

Adenoviruses are emerging pathogens which may represent new indicators of microbial water quality. In the present study, environmental samples of seawater, estuarine water, and influents of sewage treatment plants underwent both standard bacteriological and viral analyses (adenovirus identification, typing and quantification) in order to evaluate the role of surface water contamination as a possible vehicle for the transmission of adenovirus, and the relevance of adenoviruses as an additional tool in water quality assessment. Qualitative PCR methods were used for the detection and typing of adenoviruses. This was done through the sequencing and phylogenetic analysis of segments of the hexon- and fiber-coding regions of the viral genome. Subsequently, quantitative PCR assays based on TaqMan probe hydrolysis technology were used to assess virus concentrations in environmental samples. Results showed a widespread presence of adenovirus in the environment, even in the absence of bacterial indicators, confirming the relevance of evaluating these viruses as possible indicators of viral contamination of water.