Rotavirus detection in environmental water samples by tangential flow ultrafiltration and RT-nested PCR

Environmental monitoring was conducted in Otranto (Italy), from January 2006 to April 2007, to monitor the circulation of rotaviruses in various water matrices (raw and treated sewage, surface waters and seawater) and to identify any correlation with the traditional bacteriological indices (faecal coliforms). The viruses were detected using tangential flow ultrafiltration and reverse transcriptase-nested polymerase chain reaction, whilst detection of feaecal coliform was performed according to standard methods. The results showed widespread viral contamination, particularly in spring, of the matrices tested, with the exception of seawater, which at all times tested negative for the presence of rotaviruses. The typing of the rotavirus strains identified the circulation in the studied area of only two genotypes: G1 (22%) and G2 (78%). The bacterial recoveries confirmed the presence of faecal pollution indicators in all examined samples, sometimes with high values. A very weak correlation was found between the presence of faecal coliforms and the circulation of rotaviruses in the environment. The presence of rotaviruses in the environmental water samples may constitute a potential health risk for the local population.