A method for detection of SARS-CoV-2 RNA in healthy human stool: a validation study Open Access (recommended)
Coryell MP, Iakiviak M, Pereira N, Murugkar PP, Rippe J, Williams DB, Heald-Sargent T, Sanchez-Pinto LN, Chavez J, Hastie JL, Sava RL, Lien CZ, Wang TT, Muller WJ, Fischbach MA, Carlson PE. A method for detection of SARS-CoV-2 RNA in healthy human stool: a validation study. Lancet Microbe. 2021;2(6):E259-E266.
Descriptions
- Resource type(s)
- Article
- Keyword
- COVID-19
- Rights
- Attribution 4.0 International
- Creator
-
Coryell, Michael P.
Iakiviak, Mikhail
Pereira, Nicole
Murugkar, Pallavi P.
Rippe, Jason
Williams, David B.
Heald-Sargent, Taylor Alis
Sanchez-Pinto, L. Nelson
Chavez, Jairo
Hastie, Jessica L.
Sava, Rosa L.
Lien, Christopher Z.
Wang, Tony T.
Muller, William J.
Fischbach, Michael A.
Carlson, Paul E., Jr.
- Abstract
-
Background Faecal shedding of SARS-CoV-2 has raised concerns about transmission through faecal microbiota transplantation procedures. Validation parameters of authorised tests for SARS-CoV-2 RNA detection in respiratory samples are described in product labelling, whereas the published methods for SARS-CoV-2 detection from faecal samples have not permitted a robust description of the assay parameters. We aimed to develop and validate a test specifically for detection of SARS-CoV-2 in human stool. Methods In this validation study, we evaluated performance characteristics of a reverse transcriptase real-time PCR (RT-rtPCR) test for detection of SARS-CoV-2 in human stool specimens by spiking stool with inactivated SARS-CoV-2 material. A modified version of the US Centers for Disease Control and Prevention RT-rtPCR SARS-CoV-2 test was used for detection of viral RNA. Analytical sensitivity was evaluated in freshly spiked stool by testing two-fold dilutions in replicates of 20. Masked samples were tested by a second laboratory to evaluate interlaboratory reproducibility. Short-term (7-day) stability of viral RNA in stool samples was assessed with four different stool storage buffers (phosphate-buffered saline, Cary-Blair medium, Stool Transport and Recovery [STAR] buffer, and DNA/RNA Shield) kept at -80 degrees C, 4 degrees C, and ambient temperature (approximately 21 degrees C). We also tested clinical stool and anal swab specimens from patients who were SARS-CoV-2 positive by nasopharyngeal testing. Findings The lower limit of detection of the assay was found to be 3000 viral RNA copies per g of original stool sample, with 100% detection across 20 replicates assessed at this concentration. Analytical sensitivity was diminished by approximately two times after a single freeze-thaw cycle at -80 degrees C. At 100 times the limit of detection, spiked samples were generally stable in all four stool storage buffers tested for up to 7 days, with maximum changes in mean threshold cycle values observed at -80 degrees C storage in Cary-Blair medium (from 29.4 [SD 0.27] at baseline to 30.8 [0.17] at day 7; p<0.0001), at 4 degrees C storage in DNA/RNA Shield (from 28.5 [0.15] to 29.8 [0.09]; p=0.0019), and at ambient temperature in STAR buffer (from 30.4 [0.24] to 32.4 [0.62]; p=0.0083). 30 contrived SARS-CoV-2 samples were tested by a second laboratory and were correctly identified as positive or negative in at least one of two rounds of testing. Additionally, SARS-CoV-2 RNA was detected using this assay in the stool and anal swab specimens of 11 of 23 individuals known to be positive for SARS-CoV-2. Interpretation This is a sensitive and reproducible assay for detection of SARS-CoV-2 RNA in human stool, with potential uses in faecal microbiota transplantation donor screening, sewage monitoring, and further research into the effects of faecal shedding on the epidemiology of the COVID-19 pandemic. Copyright Published by Elsevier Ltd.
- Related URL
- Publisher
-
ELSEVIER
- Date Created
-
2021-06
- Original Identifier
- (PMID) 33821247
- Grants and funding
-
National Institute of Allergy and Infectious Diseases, US National Institutes of HealthUnited States Department of Health & Human ServicesNational Institutes of Health (NIH) - USANIH National Institute of Allergy & Infectious Diseases (NIAID); Center for Biologics Evaluation and Research, US Food and Drug Administration
- DOI
-
10.1016/S2666-5247(21)00059-8
File Details
- File Properties
-
Mime type: application/pdf
File size: 520.9 kB