Detection of echovirus 7 in effluent sewage treatment plant Ahvaz city, Iran

Golnaz Mokhtari Irani; Azarakhsh Azaran; Roya Pirmoradi; Alireza Tabibzadeh; Mohamad Rashno; Manoochehr Makvandi

doi:10.18502/ijm.v18i1.20938

Golnaz Mokhtari Irani Cellular and Molecular Research Center, Medical Basic Sciences Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
Azarakhsh Azaran Department of Virology, School of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
Roya Pirmoradi Department of Virology, School of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
Alireza Tabibzadeh Department of Medical Laboratory Sciences, Faculty of Medical Sciences, Islamic Azad University, Arak Branch, Arak, Iran
Mohamad Rashno Cellular and Molecular Research Center, Medical Basic Sciences Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
Manoochehr Makvandi Cellular and Molecular Research Center, Medical Basic Sciences Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran

DOI: https://doi.org/10.18502/ijm.v18i1.20938

Keywords: Wastewater; Environment; Enterovirus; Polymerase chain reaction

Abstract

Background and Objectives: The enteroviruses may lead to conditions such as aseptic meningitis, encephalitis, acute flac- cid myelitis, epidemic pleurodynia (Bornholm disease), hemorrhagic conjunctivitis, and myopericarditis among pediatric populations. The present study was undertaken to identify the presence of enteroviruses within sewage treatment systems.

Materials and Methods: 24 composite effluent sewage samples (500 ml each) were collected, centrifuged (1000 rpm for 30 minutes), and the first supernatant was saved. The precipitate was resuspended in 10 ml of supernatant, treated with 10% chloroform, and centrifuged again (1000 rpm for 5 minutes) to collect a second supernatant. The first and second supernatants were combined, treated with 2.2% sodium chloride and 7% polyethylene glycol 6000, and the mixture was agitated at 4°C overnight before being centrifuged for two hours at 2000 g. After discarding the supernatant, the pellet was resuspended at a 1:100 dilution. Each sample was then inoculated into RD and HeLa cells for virus isolation, followed by detection via RT- PCR. A phylogenetic tree was constructed to determine the genotypes of the isolated enteroviruses.

Results: Enterovirus was detected in 10 of 24 (41.7%) sewage effluent samples. Phylogenetic analysis of five randomly chosen positive samples identified echovirus 7.

Conclusion: The removal of enteroviruses during the sewage treatment process is of paramount importance, necessitating heightened attention to this critical phase of wastewater management.