Abstract
Data on the performance of saliva specimens for diagnosing coronavirus disease 2019 (COVID-19) in ambulatory patients are scarce and inconsistent. We assessed saliva-based specimens for detecting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by reverse transcriptase PCR (RT-PCR) in the community setting and compared three different collection methods. This prospective study was conducted in three primary care centers. RT-PCR was performed on paired nasopharyngeal swabs (NPS) and saliva samples collected from outpatients with a broad clinical spectrum of illness. To assess differences in collection methods, saliva specimens were obtained in a different way in each of the participating centers: supervised collection (SVC), oropharyngeal washing (OPW), and self-collection (SC). Pairs of NPS and saliva samples from 577 patients (median age, 39 years; 44% men; 42% asymptomatic) were collected and tested, and 120 (20.8%) gave positive results. The overall agreement with NPS results and kappa coefficients (κ) for saliva samples obtained by SVC, OPW, and SC were 95% (κ = 0.85), 93.4% (κ = 0.76), and 93.3% (κ = 0.76), respectively. The sensitivities (95% confidence intervals [95% CI]) of the saliva specimens ranged from 86% (72.6% to 93.7%) for SVC to 66.7% (50.4% to 80%) for SC samples. Sensitivity was higher for samples with lower cycle threshold ( C T ) values. The best RT-PCR performance was observed for SVC, with sensitivities (95% CI) of 100% (85.9% to 100%) in symptomatic individuals and 88.9% (50.7% to 99.4%) in asymptomatic individuals at C T values of ≤30. We conclude that saliva is an acceptable specimen for the detection of SARS-CoV-2 in the community setting. Specimens collected under supervision perform comparably to NPS and can effectively identify individuals at higher risk of transmission under real-life conditions.
Keywords: COVID-19; PCR; SARS-CoV-2; diagnostics; saliva.
【저자키워드】 COVID-19, SARS-CoV-2, Saliva, diagnostics, PCR, 【초록키워드】 coronavirus disease, Saliva, Coronavirus disease 2019, coronavirus, Prospective Study, Transmission, severe acute respiratory syndrome Coronavirus, RT-PCR, Nasopharyngeal swab, sensitivity, Asymptomatic individuals, Asymptomatic, cycle threshold, nasopharyngeal swabs, Patient, Community, outpatients, Oropharyngeal, respiratory, reverse transcriptase PCR, Outpatient, best, reverse transcriptase, community setting, confidence interval, acute respiratory syndrome, higher risk, 95% CI, acute respiratory syndrome coronavirus, acute respiratory syndrome coronavirus 2, ambulatory patients, median age, individual, specimen, symptomatic individuals, primary care centers, coefficient, sensitivities, saliva samples, pair, diagnosing, positive, intervals, saliva specimens, NPs, asymptomatic individual, tested, identify, collected, conducted, was performed, conditions, ranged, ambulatory patient, saliva specimen, symptomatic individual, 【제목키워드】 detection, performance, Sample, Collection,