J Med Virol. 2021 Feb 2. doi: 10.1002/jmv.26839. Online ahead of print.
ABSTRACT
Current diagnostic standards involve SARS-CoV-2 detection in nasopharyngeal swabs (NPS), but saliva is an attractive and non-invasive option for diagnosis. The objectives were to determine the performance of saliva in comparison to NPS for detecting SARS-CoV-2 and to compare the optimized home brew RT-PCR with a commercial RT-PCR. Paired NPS and saliva specimens were prospectively collected and tested by RT-PCR from patients presenting at an emergency room with signs and symptoms compatible with COVID-19. A total of 348 samples from 174 patients were tested by RT-PCR assays. Among 174 patients with symptoms, 63 (36%) were SARS-CoV-2 positive in NPS using the optimized home-brew PCR. Of these 63 patients, 61 (98%) were also positive in saliva. An additional positive SARS-CoV-2 saliva was detected in a patient with pneumonia. Kappa Cohen's coefficient agreement between NPS and saliva was 0.96 (95%CI 0.90-0.99). Median Ct values in NPS versus saliva were 18.88 (IQR 15.60-23.58; Range: 11.97-38.10) versus 26.10 (IQR 22.75-30.06; Range: 13.78-39.22), respectively (p < 0.0001). The optimized home-brew RT-PCR demonstrated higher analytical and clinical sensitivity compared to the commercial RT-PCR assay. A high sensitivity (98%) and agreement (kappa 0.96) in saliva samples compared to NPS was demonstrated when using an optimized home-brew PCR even when the viral load in saliva was lower than in NPS. This non-invasive sample is easy to collect, requires less consumable and avoids discomfort to patients. Importantly, self-collection of saliva can diminish exposure to healthcare personnel. This article is protected by copyright. All rights reserved.
PMID:33527375 | DOI:10.1002/jmv.26839