2022 · Journal of clinical microbiology · open access
Quantitative SARS-CoV-2 Viral-Load Curves in Paired Saliva Samples and Nasal Swabs Inform Appropriate Respiratory Sampling Site and Analytical Test Sensitivity Required for Earliest Viral Detection
Savela et al.
The finding, in our words
Among unvaccinated household contacts, self-collected saliva microsampling with a high-sensitivity assay detected SARS-CoV-2 infection up to 4.5 days before nasal swabs became positive on low-sensitivity tests, because nasal viral loads were initially low despite later peaking higher. High-sensitivity saliva testing therefore offers the most reliable early detection, informing patient-centric decentralised strategies for screening and surveillance.
A paraphrase to the Library’s standard, never the abstract. The source is one link away and is always the authority.
The study found that self-collected dried saliva on FishburneTabs achieved 92% accuracy for viral RNA detection compared to standard liquid saliva samples. This method supports decentralised testing by enabling reliable sample storage and transport for upper respiratory infections.
The COVID-19 pandemic accelerated adoption of decentralised testing and self-collected saliva specimens, but revealed challenges with variable diagnostic accuracy and lack of internationally standardised processing protocols. Stricter regulatory oversight and robust diagnostic stewardship are needed to balance broad access with clinical performance.
This review summarises how incorporating saliva and urine into home-based point-of-care systems expands diagnostic accessibility for dengue virus, aligning with the WHO REASSURED framework for affordable and rapid testing.
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.
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.