Sabzchi-Dehkharghani Hamed, Samadi Kafil Hossein, Majnooni-Heris Abolfazl, Akbarzadeh Abbas, Naderi-Ahranjani Rana, Fakherifard Ahmad, Mosaferi Mohammad, Gilani Neda, Noury Mojtaba, Eydi Parisa, Sayyari Sis Sajjad, Toghyanian Nasimolzahra, Yegani Reza
Department of Water Engineering, Faculty of Agriculture, University of Tabriz, Tabriz, Iran.
Drug Applied Research Center, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran.
Sustain Water Resour Manag. 2023;9(1):21. doi: 10.1007/s40899-022-00809-8. Epub 2022 Dec 17.
It is crucial to have access to clean water resources during the COVID-19 pandemic for hygiene, since virus infection through wastewater leaks in metropolitan areas can be a threat. Accurate monitoring of urban water resources during the pandemic seems to be the only way to confirm safe and infected resources. Here, in this study, the amount of Severe Acute Respiratory Syndrome Coronavirus 2's Ribonucleic Acid (SARS-CoV-2 RNA) in the Tabriz urban water network located in the northwest of Iran was investigated by an extensive sampling of the city's water sources at a severe peak of the COVID-19 pandemic. The sampling process comprised a range of water sources, including wells, qanats, water treatment facilities, dams, and reservoirs. For each sample, a combination of polyethylene glycol (PEG) and sodium chloride (NaCl) was used for concentration and a laboratory RNA-based method was conducted for quantification. Before applying the extraction and quantification procedure to real samples, the proposed concentration method was verified with synthetic serum samples for the first time. After the concentration, RNA extraction was done by the BehPrep extraction column method, and Reverse Transcription Polymerase Chain Reaction (RT-PCR) detection of the virus was done by Covitech COVID-19 RT-PCR kit. In none of the water supply resources, SARS-COV-2 RNA has been detected except in a sample grabbed from a well adjacent to an urban wastewater discharge point downstream. The results of molecular analysis for the positive sample showed that the CT value and concentration of the virus genome were equal to 32.57 and 5720 copies/L, respectively. Quantitative analysis of real samples shows that the city's water network was safe at the time of the study. However, given that the positive sample was exposed to wastewater leakage, periodic sampling from wells and qanats is suggested during the pandemic until it can be proven that the leakage to these water sources is impossible.
在新冠疫情期间，获取清洁水资源以保持卫生至关重要，因为大城市地区废水泄漏导致病毒感染可能构成威胁。疫情期间对城市水资源进行准确监测似乎是确认安全和受感染水源的唯一途径。在此项研究中，在新冠疫情严重高峰期，通过对伊朗西北部大不里士市的水源进行广泛采样，调查了该市城市供水网络中严重急性呼吸综合征冠状病毒2（SARS-CoV-2）的核糖核酸（RNA）含量。采样过程涵盖了一系列水源，包括水井、坎儿井、水处理设施、水坝和水库。对于每个样本，使用聚乙二醇（PEG）和氯化钠（NaCl）的组合进行浓缩，并采用基于实验室RNA的方法进行定量。在将提取和定量程序应用于实际样本之前，首次用合成血清样本对所提出的浓缩方法进行了验证。浓缩后，通过BehPrep提取柱法进行RNA提取，并使用Covitech新冠病毒RT-PCR试剂盒对病毒进行逆转录聚合酶链反应（RT-PCR）检测。除了从下游城市污水排放点附近的一口井采集的一个样本外，在所有供水水源中均未检测到SARS-CoV-2 RNA。阳性样本的分子分析结果表明，病毒基因组的CT值和浓度分别为32.57和5720拷贝/升。实际样本的定量分析表明，在研究期间该市的供水网络是安全的。然而，鉴于阳性样本暴露于废水泄漏，建议在疫情期间对水井和坎儿井进行定期采样，直到可以证明这些水源不可能发生泄漏为止。
