Improved SARS-CoV-2 RNA recovery in wastewater matrices using a CTAB-based extraction method

OUSSET J; PIANCIOLA LA; MAZZEO M; OTEIZA JM; JAUREGUIBERRY MS; VENTURINO A; BARRIL PA

Journal of Virological Methods

Elsevier B.V.

Año: 2024 vol. 327

Wastewater-based epidemiology has allowed tracking the magnitude and distribution of SARS-CoV-2 in communities,allowing public health officials to prepare for impending outbreaks. While many factors influencerecovery of SARS-CoV-2 from wastewater, proper extraction, concentration, and purification of RNA are keysteps to ensure accurate detection of viral particles. The aim of this study was to compare the efficiency of fourcommonly used RNA extraction methods for detection of the SARS-CoV-2 RNA genome in sewage samplesartificially inoculated with the virus, in order to identify a protocol that improves viral recovery. These methodsincluded CTAB-based, TRIzol-based, and guanidinium thiocyanate (GTC)-based extraction procedures coupledwith silica spin column-based purification, and an automated extraction/purification protocol using paramagneticparticles. Following RNA extraction, virus recovery rates were compared using RT-qPCR-baseddetection. The CTAB-based approach yielded the highest recovery rates and was the only method to consistentlydemonstrate stable virus recovery percentages regardless of the specific physicochemical characteristics ofthe samples tested. The TRIzol method proved to be the second most effective, yielding significantly higherrecovery rates compared to both the GTC-based and the automated extraction methods. These results suggestthat the CTAB-based approach could be a useful tool for the recovery of viral RNA from complex wastewatermatrices.