Deep throat saliva as an alternative diagnostic specimen type for the detection of SARS-CoV-2.

Nasopharyngeal swabs (NPS) are widely accepted as specimens for the detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in the current pandemic of coronavirus disease 2019. However, the collection procedures for NPS specimens causes sneezing and coughing in most patients, which generate droplets or aerosol particles that are hazardous to the healthcare workers collecting these specimens. In this study, 95 patient-matched paired deep throat saliva (DTS) and NPS specimens from 62 patients were analyzed. Samples were tested for SARS-CoV-2 by reverse-transcription polymerase chain reaction (RT-PCR). The rates of detection for DTS (53.7%) and NPS (47.4%) samples were comparable (P = .13). It is important to note that the patients should be clearly instructed or supervised during DTS collection. In conclusion, SARS-CoV-2 detection by RT-PCR was equivalent in DTS and NPS specimens.

Evaluation of the Xpert Xpress SARS-CoV-2/Flu/RSV Assay for Simultaneous Detection of SARS-CoV-2, Influenza A and B Viruses, and Respiratory Syncytial Virus in Nasopharyngeal Specimens.

Patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), influenza A (flu A), influenza B (flu B), and respiratory syncytial virus (RSV) have overlapping clinical presentations, but the approaches to treatment and management of infections caused by these viruses are different. Therefore, rapid diagnosis in conjunction with infection prevention measures is important to prevent transmission of the diseases. Recently, a new Xpert Xpress SARS-CoV-2/Flu/RSV (Xpert 4-in-1) assay enables the detection and differentiation of SARS-CoV-2, flu A, flu B, and RSV in upper respiratory tract specimens. In this study, we evaluated the performance of the Xpert 4-in-1 assay by comparing it with that of the Xpert Xpress SARS-CoV-2 and Xpert Xpress Flu/RSV assays for the detection of the four viruses in nasopharyngeal (NP) specimens. A total of 279 NP specimens, including 66, 56, 64, and 53 specimens positive for SARS-CoV-2, flu A, flu B, and RSV, respectively, were included. The Xpert 4-in-1 assay demonstrated high concordance with the comparator assays, with overall agreement for SARS-CoV-2, flu A, flu B, and RSV at 99.64%, 100%, 99.64%, and 100%, respectively, and a high Cohen's kappa (κ) value ranging from 0.99 to 1.00, indicating an almost perfect correlation between assays. The cycle threshold value association between positive samples also showed a good correlation between assays. In conclusion, the overall performance of the Xpert 4-in-1 assay was highly comparable to that of the Xpert SARS-CoV-2 and Xpert Flu/RSV assays for the detection and differentiation of SARS CoV-2, flu A, flu B, and RSV in NP specimens.