ABSTRACT
Since the beginning of the COVID-19 pandemic, molecular diagnostics of SARS-CoV-2 have taken center stage in the detection of infected individuals for isolation purposes but also in the mass surveillance as a preventive strategy to contain the virus spread. While nasopharyngeal swabs (NPS) have remained the golden standard substrate, salivary diagnostic for SARS-CoV-2 has been proposed as an alternative and non-invasive measure in vulnerable individuals. Nevertheless, there is a widespread assumption that salivary RT-PCR does not match the quality of testing using NPS and particular care should be taken in respect to food or beverage intake, when sampling saliva. Our study indicates that without any precaution in the selection of 190 patients, nor restriction over the time-window of sampling, there is 99% match in the COVID-19 positivity between NPS and saliva when using RT-PCR, with a reported Delta in thermal cycles (Cts) values for the viral genes Envelop e (E) and Open reading frame 1ab (Orf1ab) between 0 and 2, a 98.7% Sensitivity and 100% Specificity. This high accuracy is maintained in pooling configurations that can be used for mass-testing purposes in professional and educational settings. The further advantage to using crude saliva as compared to NPS or mouthwash is that direct methods yield robust results. Overall, our study validates and promotes the use of salivary diagnostic for COVID-19 eliminating the need of a medical practitioner for the sampling, resolving the unpleasantness of the NPS intervention and empowering the patient to do self-testing in times of need.
This article is protected by copyright. All rights reserved.
No comments:
Post a Comment