Download This Paper
Preprints with The Lancet is a collaboration between The Lancet Group of journals and SSRN to facilitate the open sharing of preprints for early engagement, community comment, and collaboration. Preprints available here are not Lancet publications or necessarily under review with a Lancet journal. These preprints are early-stage research papers that have not been peer-reviewed. The usual SSRN checks and a Lancet-specific check for appropriateness and transparency have been applied. The findings should not be used for clinical or public health decision-making or presented without highlighting these facts. For more information, please see the FAQs.
Comparative Evaluation of Rapid Salivary RT-LAMP Assay for Screening of SARS-CoV-2 Infection
22 Pages Posted: 9 Feb 2021
More...Abstract
Background: Response to the COVID-19 outbreak calls for rapid and accurate diagnostic tests to control the pandemic outbreak. We aimed to evaluate saliva specimen as well as rapid RT-LAMP test for diagnosis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection.
Methods: This monocentric study screened outpatients that were either symptomatic or contact-cases of a COVID-19 confirmed case.Nasopharyngeal-swabs (NPS) and saliva were collected simultaneously and tested by RT-qPCR. Saliva samples were also analyzed using an extraction-free rapid RT-LAMP test (EasyCOV®). Infected participants were those with a positive (Ct value <35) NP and/or salivary RT-qPCR (Composite Reference Test, CRTest).
Findings: Between the 1st September and the 7th of October 2020, samples of 443 adults were collected and analyzed. The mean age was 32·2 years, 59·4% declared mild symptoms at the time of sampling and 40·6% were asymptomatic. Positivity rate of NP and/or salivary RT-qPCR was 16·0% (71/443) and the concordance between these two methods was 87·3%. Sensitivity and specificity of RT-LAMP compared to CRTest were 85·9% (95% CI 77·8%-94·0%) and 99·5% (98·7%-100%), respectively. RT-LAMP accuracy was 91·0% and 98·2% compared to NP and salivary RT-qPCR, respectively. All 52 participants with a salivary RT-qPCR Ct value <31 were positive by RT-LAMP. Performances of RT-LAMP for symptomatic and asymptomatic participants were similar.
Interpretation: We demonstrated that self-collected saliva and a rapid RT-LAMP-based field test are reliable alternatives for SARS-CoV-2 detection. Their use could complement, simplify and accelerate COVID-19 diagnostics.
Clinical Trial Registration: NCT04337424
Funding Statement: SkillCell, CNRS, Region Occitanie
Declaration of Interests: Dr. J Reynes reports personal fees from Gilead company, personal fees
from ViiV Healthcare company, personal fees from MSD Company, personal
fees from Pfizer Company, personal fees from Theratechnologies
Company, outside the submitted work.
Dr. F Molina reports grants from SkillCell ; personal fees from
SkillCell, outside the submitted work. In addition, Dr. Molina has a
patent Patent # EP20166524 pending.
Dr. J Espeut, Dr. J Baptiste and Dr. F Santos Schneider reports
personal fees from SkillCell, outside the submitted work
The other authors declared no competing interest.
Ethics Approval Statement: The study was approved by a French ethic committee (CPP-lle de France XI) on April 03, 2020 and a substantial modification was approved on May 11, 2020.
Suggested Citation: Suggested Citation