Saliva as a Candidate for COVID-19 Diagnostic Testing: A Meta-Analysis

Abstract

Objectives: Our aim was to conduct a meta-analysis on the reliability and consistency of SARS-CoV-2 viral RNA detection in saliva specimens. Methods: We reported our meta-analysis according to the Cochrane Handbook. We searched the Cochrane Library, Embase, Pubmed, Scopus, Web of Science and clinical trial registries for eligible studies published between 1 January and 25 April 2020. The number of positive tests and total number of conducted tests were collected as raw data. The proportion of positive tests in the pooled data were calculated by score confidence interval estimation with the Freeman-Tukey transformation. Heterogeneity was assessed using the I2 measure and the Chi2 test. Results: The systematic search revealed 96 records after removal of duplicates. 26 records were included for qualitative analysis and 5 records for quantitative synthesis. We found 91% (95%CI = 80%-99%) sensitivity for saliva tests and 98% (95%CI 89%-100%) sensitivity for nasopharyngeal swab (NPS) tests in previously confirmed COVID-19 infected patients, with moderate heterogeneity among studies. Additionally, we identified 18 registered, ongoing clinical trials on saliva-based tests for detection of the virus. Conclusion: Saliva tests offer a promising alternative to NPS for COVID-19 diagnosis. However, further diagnostic accuracy studies are needed to improve their specificity and sensitivity.

Saliva specimens for detection of severe acute respiratory syndrome coronavirus 2 in Kuwait: A cross-sectional study

“…This data seem in agreement with previous cross-sectional study (sensitivity and specificity of the saliva sample RT-PCR are 84.2 % and 98.9 %, respectively) [ 12 ]. Furthermore, in recent meta-analysis, the sensitivities for SARS-CoV-2 were 91 % (95 % CI, 80–99 %) and 98 % (95 % CI, 89–100 %) for saliva and for NPS samples, respectively [ 25 ]. Interestingly, Kim and al.…”

Frequency and Duration of SARS-CoV-2 Shedding in Oral Fluid Samples Assessed by a Modified Commercial Rapid Molecular Assay

“…Several recent studies have showed that OF could be an appropriate sample for diagnosis of SARS-CoV-2 [ 6 , 22 ]. The meta-analysis by Czumbel et al on the reliability and consistency of SARS-CoV-2 viral RNA detection in OF specimens found 91% (95%CI = 80%–99%) sensitivity for OF tests and 98% (95%CI 89%–100%) sensitivity for NPS in previously confirmed COVID-19 infected patients [ 22 ].…”

Hospital Preparedness for COVID-19: The Known and The Known Unknown

“…22,23 Several preprint articles have reported that the sensitivity of a single RT-PCR test with saliva for diagnosing COVID-19 was in the range 50%-90%; consequently, further studies are warranted. 24,25 Abnormal laboratory results, such as lymphopenia or elevated D-dimer levels, are insufficient to exclude or confirm COVID-19. 1,26 Although typical chest X-ray findings, including interstitial changes and ground-glass opacities located in the bilateral lower lobes, have been reported in patients with COVID-19, a retrospective study revealed that chest X-rays showed no abnormalities in 58.3% of patients with COVID-19.…”