The Occurrence of Sars-Cov-2 in Tehran’S Municipal Wastewater: Performance of Treatment Systems and Feasibility of Wastewater-Based Epidemiology Publisher

Summary: Can wastewater track COVID? Study finds WWTPs fully eliminate SARS-CoV-2 RNA post-treatment. #WastewaterEpidemiology #SARSCoV2

Hadi M¹ ; Kheiri R² ; Baghban M³ ; Sayahi A⁴ ; Nasseri S¹ ; Alimohammadi M^{1, 6} ; Khastoo H⁴ ; Aminabad MS¹ ; Vaghefi KA⁷ ; Vakili B⁸ ; Tashauoei H⁹ ; Borji SH¹ ; Iravani E⁶
Source: Journal of Environmental Health Science and Engineering Published:2024

Abstract

Analyzing municipal wastewater for the presence of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) helps to evaluate the efficacy of treatment systems in mitigating virus-related health risks. This research investigates wastewater treatment plants’ (WWTPs) performance in the reduction of SARS-CoV-2 from municipal wastewater in Tehran, Iran. SARS-CoV-2 RNA was measured within sewers, at the inlets, and after the primary and secondary treatment stages of three main WWTPs. Within sewers, the average virus titer stood at 58,600 gc/L, while at WWTP inlets, it measured 38,136 gc/L. A substantial 67% reduction in virus titer was observed at the inlets, accompanied by a 2-log reduction post-primary treatment. Remarkably, the biological treatment process resulted in complete virus elimination across all plants. Additionally, a notable positive correlation (r > 0.8) was observed between temperature and virus titer in wastewater. Using wastewater-based epidemiology (WBE) technique and the estimated SARS-CoV-2 RNA shedding rates, the infection prevalence among populations served by WWTPs found to be between 0.128% to 0.577%. In conclusion, this research not only advances our understanding of SARS-CoV-2 dynamics within wastewater treatment systems but also provides practical insights for enhancing treatment efficiency and implementing the feasibility of WBE strategies in Tehran. These implications contribute to the broader efforts to protect public health and mitigate the impact of future viral outbreaks. Graphical abstract: (Figure presented.) © The Author(s), under exclusive licence to Tehran University of Medical Sciences 2024.