Clinical Performance of the cobas Liat SARS-CoV-2 & Influenza A/B Assay in Nasal Samples

Abstract

Background and Objective Point-of-care type molecular diagnostic tests have been used for detecting SARS-CoV-2, although their clinical utility with nasal samples has yet to be established. This study evaluated the clinical performance of the cobas Liat SARS-CoV-2 & Influenza A/B (Liat) assay in nasal samples. Methods Nasal and nasopharyngeal samples were collected and were tested using the Liat, the cobas 6800 system and the cobas SARS-CoV-2 & Influenza A/B (cobas), and a method developed by National Institute of Infectious Diseases, Japan (NIID). Results A total of 814 nasal samples were collected. The Liat assay was positive for SARS-CoV-2 in 113 (13.9%). The total, positive, and negative concordance rate between the Liat and cobas/NIID assays were 99.3%/98.4%, 99.1%/100%, and 99.3%/98.2%, respectively. Five samples were positive only using the Liat assay. Their Ct values ranged from 31.9 to 37.2. The Ct values of the Liat assay were significantly lower ( p < 0.001) but were correlated ( p < 0.001) with those of other molecular assays. In the participants who tested positive for SARS-CoV-2 on the Liat assay using nasopharyngeal samples, 88.2% of their nasal samples also tested positive using the Liat assay. Conclusion The Liat assay showed high concordance with other molecular assays in nasal samples. Some discordance occurred in samples with Ct values > 30 on the Liat assay. Supplementary Information The online version contains supplementary material available at 10.1007/s40291-022-00580-8.

Analytical performance of the rapid qualitative antigen kit for the detection of SARS-CoV-2 during widespread circulation of the Omicron variant

“…However, the Ct stratified sensitivity of the QuickNavi-COVID19 Ag is almost equal to that of BinaxNOW for the Omicron variant. In the analytical evaluation of BinaxNOW, anterior nasal samples were used for the evaluation and the viral load of anterior nasal samples has been reported to be much lower than that of nasopharyngeal samples [ 27 , 28 ], which is considered to be the gold standard and which was used in this study. We consider that the difference of the samples caused the difference in sensitivity.…”

Evaluation of the Kaira COVID-19/Flu/RSV Detection Kit for detection of SARS-CoV-2, influenza A/B, and respiratory syncytial virus: A comparative study with the PowerChek SARS-CoV-2, influenza A&B, RSV Multiplex Real-time PCR Kit

“…Given the changes in the epidemiology of influenza and RSV, molecular assays to simultaneously detect these viruses and SARS-CoV-2 are urgently needed and should be performed throughout the year. Currently, various molecular assays to simultaneously detect SARS-CoV-2 and other respiratory viruses are commercially available, most of which are sample-to-result rRT-PCR assays [11][12][13][14][15][16][17][18][19][20][21]. Sample-to-result assays such as the RP2.1 and Xpert Xpress SARS-CoV-2/Flu/RSV assays are simple to perform and do not require skilled personnel.…”

“…Furthermore, co-infection of SARS-CoV-2 and other respiratory viruses can occur, albeit at a low rate [9,10]. To address this situation, various molecular assays to simultaneously detect SARS-CoV-2 and other respiratory viruses have been developed and are widely used in clinical settings [11][12][13][14][15][16][17][18][19][20][21].…”

A prospective evaluation of three saliva qualitative antigen testing kits for the detection of SARS-CoV-2 in Japan

“…NP and saliva samples were simultaneously obtained from participants. The sample collection was performed as previously described [2,[8][9][10][11][12][13][14][15][16][17][18][19]. All antigen tests for saliva were immediately performed on site after sample collection.…”