Effect of storage conditions on SARS-CoV-2 RNA quantification in wastewater solids

PeerJ

article

Adrian Simpson¹  Aaron Topol¹  Bradley J. White¹  Marlene K. Wolfe²  Krista R. Wigginton³  Alexandria B. Boehm² 

[1] Verily Life Sciences;Stanford University;University of Michigan - Ann Arbor

关键词: COVID-19;    SARS-CoV-2;    Wastewater;    Wastewater-based epidemiology;    Freeze-thaw;    Settled solids;   

DOI  :  10.7717/peerj.11933

学科分类：社会科学、人文和艺术（综合）

来源: Inra

【 摘 要 】

SARS-CoV-2 RNA in wastewater settled solids is associated with COVID-19 incidence in sewersheds and therefore, there is a strong interest in using these measurements to augment traditional disease surveillance methods. A wastewater surveillance program should provide rapid turn around for sample measurements (ideally within 24 hours), but storage of samples is necessary for a variety of reasons including biobanking. Here we investigate how storage of wastewater solids at 4 °C, −20 °C, and −80 °C affects measured concentrations of SARS-CoV-2 RNA. We find that short term (7 or 8 d) storage of raw solids at 4 °C has little effect on measured concentrations of SARS-CoV-2 RNA, whereas longer term storage at 4 °C (35–122 d) or freezing reduces measurements by 60%, on average. We show that normalizing SARS-CoV-2 RNA concentrations by concentrations of pepper mild mottle virus (PMMoV) RNA, an endogenous wastewater virus, can correct for changes during storage as storage can have a similar effect on PMMoV RNA as on SARS-CoV-2 RNA. The reductions in SARS-CoV-2 RNA in solids during freeze thaws is less than those reported for the same target in liquid influent by several authors.

【 授权许可】

CC BY