Performance evaluation of the point-of-care SAMBA II SARS-CoV-2 Test for detection of SARS-CoV-2

Assennato, S. M.; Ritchie, A. V.; Nadala, C.; Zhang, H.; Datir, R.; Gupta, R. K.; Curran, M. D.; Lee, H. H.; Goel, N.

Background: Nucleic acid amplification for the detection of SARS-CoV-2 RNA in respiratory samples is the standard method for diagnosis. These tests are centralised and therefore turnaround times can be 2-5 days. Point-of-care testing with rapid turnaround times would allow more effective triage in settings where patient management and infection control decisions need to be made rapidly. Methods: Analytical and clinical sensitivity and specificity of the SAMBA II SARS-CoV-2 Test was evaluated on panels and residual clinical samples. The clinical performance was compared to the Public Health England reference tests. Results: The limit of detection of the SAMBA II SARS-CoV-2 Test is 250 cp/mL and is specific for detection of 2 regions of the SARS-CoV-2 genome. The clinical sensitivity was evaluated in 172 clinical samples provided by Public Health England, Cambridge, which showed a sensitivity of 98.9% (95% CI 94.03-99.97%), specificity of 100% (95% CI 95.55-100%), PPV of 100% and NPV of 98.78% (92.02-99.82%) compared to testing by Public Health England (PHE). SAMBA detected 3 positive samples that were initially negative by PHE. Discussion: The data shows that the SAMBA II SARS-CoV-2 Test performs equivalently to the centralised testing methods with a much quicker turnaround time. Point of care testing, such as SAMBA, should enable rapid patient management and effective implementation of infection control measures.