Spatial and Temporal Trends of SARS-CoV-2 RNA from Wastewater Treatment Plants over 6 Weeks in Cape Town, South Africa

Abstract

Recent scientific trends have revealed that the collection and analysis of data on the occurrence and fate of SARS-CoV-2 in wastewater may serve as an early warning system for COVID-19. In South Africa, the first COVID-19 epicenter emerged in the Western Cape Province. The City of Cape Town, located in the Western Cape Province, has approximately 4 million inhabitants. This study reports on the monitoring of SARS-CoV-2 RNA in the wastewater of the City of Cape Town’s wastewater treatment plants (WWTPs) during the peak of the epidemic. During this period, the highest overall median viral RNA signal was observed in week 1 (9200 RNA copies/mL) and declined to 127 copies/mL in week 6. The overall decrease in the amount of detected viral SARS-CoV-2 RNA over the 6-week study period was associated with a declining number of newly identified COVID-19 cases in the city. The SARS-CoV-2 early warning system has now been established to detect future waves of COVID-19.

Utilization of SARS-CoV-2 Wastewater Surveillance in Africa—A Rapid Review

“…These articles were imported into Convidence and nine duplicates were removed, leaving 35 articles included in the abstract screening. A total of 23 studies were excluded following abstract screening, leaving 12 articles [ 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 ] for full-text screening. Four articles [ 27 , 28 , 30 , 34 ] were excluded after full-article screening, leaving eight articles for data extraction ( Supplementary Table S1 ).…”

“…Of the eight articles included in the study, four were from South Africa [ 29 , 31 , 33 , 38 ], two from Morocco [ 35 , 36 ], and one each from Cameroon [ 32 ] and Tunisia [ 37 ]. Three were cross-sectional studies [ 29 , 33 , 37 ], four were reviews [ 32 , 35 , 36 , 38 ], and one was a short communication/proof-of-concept piece [ 31 ]. More details are presented in Supplementary Table S1 .…”

“…Of the four studies that collected and analyzed wastewater, three were conducted in South Africa [ 29 , 31 , 33 ] and one in Tunisia [ 37 ]. In all four studies, SARS-CoV-2 was extracted from municipal wastewater.…”

“…A study conducted to evaluate the temporospatial migration and attenuation of the SARS-CoV-2 virus using the polymerase chain reaction (PCR) in municipal wastewater in South Africa [ 29 ] utilized the 2019-nCoV genesig ® Advanced Kit (Primerdesign Ltd., Plymouth Meeting, PA, USA). Two other studies conducted in South Africa [ 31 , 33 ] utilized the RT-PCR (Whitehead Scientific, Integrated DNA Technologies, AI, USA) extraction methodology. In Tunisia, Jmii et al [ 37 ] used the Allplex 2019-nCoV kit (Seegene, Seoul, Korea) and the QuantiTect virus Kit (Qiagen, Hilden, Germany) for extraction.…”

“…In two studies [ 33 , 37 ], SARS-CoV-2 RNA was detected in raw and treated wastewater collected from different municipalities. In both studies, SARS-CoV-2 viral RNA correlated with the number of new cases in the studied areas.…”