Comparison of four concentration methods of adenovirus, norovirus and rotavirus in tap water

Human enteric viruses, as adenovirus (HAdV), norovirus (HuNoV) and rotavirus (RVA) are significant causes of gastroenteritis associated with consumption of contaminated water worldwide. Various methods have been described for their detection and monitoring in water. The aim of this study was to compare the performance of four conditions for concentrating HAdV, HuNoV and RVA from water matrices, in order to develop a single protocol that could simultaneously concentrate all target viruses from tap water. The tested conditions were based on the adsorption-elution using electronegative filters, in which we evaluated cation-coated filtration by MgCl₂ with or without acid rinse by H₂SO₄ and two elution buffers, namely NaOH and tris-glycine-beef extract. Genomic material was extracted and amplified by real-time PCR and real-time RT-PCR using commercial kits. Based on the statistical analysis of amplification results (cycles of quantification), the condition involving cation-coated filtration by MgCl₂ using electronegative filters with acid rinse by H₂SO₄ combined with NaOH elution allowed efficient recovery of both HAdV, HuNoV and RVA from tap water compared to the other conditions. These findings confirm the effectiveness of the approach used to monitor three major enteric viruses in tap water.