Single- and Two-Stage, Closed-Tube, Point-of-Care, Molecular Detection of SARS-CoV-2
Song et al.
The finding, in our words
Song and colleagues validated two molecular assays for SARS-CoV-2 detection that operate without RNA extraction: single-stage RT-LAMP detected 50 virions per reaction, while two-stage Penn-RAMP achieved tenfold better sensitivity at five virions per reaction and identified infections in patients with RT-qPCR cycle thresholds below 32. These tests enable decentralised, patient-centric screening at home or in resource-poor settings with minimal instrumentation.
A paraphrase to the Library’s standard, never the abstract. The source is one link away and is always the authority.
Oral sponge saliva RT-PCR achieved 95% sensitivity and 95% specificity compared with nasopharyngeal swabs in 3,488 symptomatic and asymptomatic adults, while buccal swab performance varied with infection history and symptoms. The rapid antigen test showed 66.9% sensitivity overall, increasing to 97% in high viral load samples. Oral sponge collection permits self-sampling without laboratory pre-analytical steps, offering a robust method for decentralised SARS-CoV-2 screening.
Althaus et al., BMC infectious diseases · source ↗
Saliva-based RT-PCR for SARS-CoV-2 achieved 100 per cent sensitivity and 97 per cent specificity against nasopharyngeal swabs, while rapid antigen testing on saliva showed comparable performance and detected 97 per cent of infectious cases with cycle threshold values of 30 or below. This supports saliva self-collection as an accurate, practical option for decentralised COVID-19 screening.
Sultana et al., Diagnostic microbiology and infectious disease (paywalled) · source ↗
In 404 symptomatic patients, self-collected nasal swabs and saliva showed almost perfect agreement with healthcare-collected nasopharyngeal swabs for detecting SARS-CoV-2 and influenza A RNA. Performance and reproducibility were favourable, and collection without viral transport media offers practical advantages for decentralised screening.
Özarslan et al., Journal of infection in developing countries (paywalled) · source ↗
SalivaDirect offers a simpler, faster RNA extraction protocol for SARS-CoV-2 detection from self-collected saliva samples, demonstrating good diagnostic performance and enabling large-scale testing in resource-limited settings without trained healthcare professionals.
In confirmed COVID-19 patients, direct RT-PCR on self-collected raw saliva detected all cases (100% sensitivity) with 94.3% concordance to nasopharyngeal swabs. Guanidine-based and guanidine-free inactivators reduced sensitivity to 65.9% and 82.9% respectively. Raw saliva offers a reliable patient-centric alternative for decentralised SARS-CoV-2 testing without sample treatment.
Katsuno et al., Journal of virological methods (paywalled) · source ↗