One-Year Wastewater-Based Study: Detection and Molecular Typing of Rotaviruses, Noroviruses and Enteroviruses in Sewage of Zahedan, Iran Publisher Pubmed



Nejati A ; Pouyandeh S ; Khodakhah F ; Soheili P ; Razaghi M ; Yousefi M ; Mollaeikandelousi Y ; Keyvanlou M ; Babak R ; Masoudi A ; Tabatabaei SM ; Mahmoudi S ; Zahraei SM ; Shahmahmoodi S
Source: Food and Environmental Virology Published:2026

Abstract

Wastewater-based epidemiology (WBE) is a useful tool for early detection of multiple pathogens and an effective method for identifying circulating pathogens in a community. To assess the presence of rotaviruses (RVs), Noroviruses (NoVs) and Enteroviruses (EVs) in wastewater, a one-year study was conducted in the city of Zahedan, Iran. A total of 24 untreated wastewater samples were collected from two collection sites between April 2023 and March 2024. These samples were subjected to virus concentration using a biphasic separation system by the polyethylene-glycol (PEG) precipitation method, followed by genome extraction and one-step TaqMan real-time RT-PCR (rRT-PCR) for RV, NoV genogroup I (NoV GI), NoV genogroup II (NoV GII) and EV. Nucleic acid from the positive samples were used for type identification by nested and semi-nested PCR, Sanger sequencing and BLASTn-NCBI analysis. The results indicated that out of the 24 samples tested, 22 samples (91.66%) for RV, 18 samples (75%) for NoV GI, 24 samples (100%) for NoV GII, and 20 samples (83.33%) for EV were positive. The identified types of RVs included: genotype G1 (6 samples) and genotype G9 (1 sample) based on the VP7 region and genotype P[8] (11 samples) based on the VP4 region. For NoV GII, the genotypes identified were P7 (2 samples), P16 (1 sample), and P17 (5 samples). Additionally, the enterovirus types identified included Echovirus 14 (2 samples), Coxsackievirus A5 (1 sample), and Coxsackievirus A22 (1 sample). This study concludes that enteric viruses are highly prevalent in Zahedan and circulate throughout the year, exhibiting significant genotypic diversity. © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2025.