Self-sampling of capillary blood for SARS-CoV-2 serology
Brown et al.
The finding, in our words
Capillary blood self-sampling showed near-perfect agreement with venous sampling for SARS-CoV-2 IgG detection, achieving a Cohen's kappa of 0.88. Samples remained stable at room temperature for seven days, and 38 of 39 participants successfully collected adequate volumes, supporting its use for decentralised serological testing.
A paraphrase to the Library’s standard, never the abstract. The source is one link away and is always the authority.
The study validated a semi-quantitative protocol for Epstein-Barr virus serology using dried blood spots, demonstrating 98.8% sensitivity and 96.5% specificity compared to paired venous serum samples. The successful validation in a self-sampling cohort confirms the suitability of this patient-centric microsampling approach for large-scale seroprevalence studies and decentralised trials.
Dried blood spot eluates showed high agreement with serum for SARS-CoV-2 IgG against Spike and Nucleocapsid (r≈0.96; qualitative φ≈0.98–1.0) and remained stable after 6–8 hours of storage, supporting use of capillary DBS for serosurveys and decentralised testing.
The study demonstrated that qPCR-based epigenetic immune cell counting from capillary dried blood spots agreed with venous blood and conventional flow cytometry in healthy donors, and then identified lymphopenia, neutrophilia and a lowered lymphocyte-to-neutrophil ratio in 103 COVID-19 patients versus 113 healthy controls, with naive B cell frequency tracking disease severity, suggesting that filter-paper blood collection could enable remote immune monitoring in home-isolated patients.
Dried blood spot sampling achieved high sensitivity and specificity for SARS-CoV-2 antibody detection with strong correlation to paired serum, enabling virtually painless, decentralised specimen collection in community and remote settings where venepuncture is difficult.
Capillary dried blood spot samples analysed with the Roche Elecsys anti-SARS-CoV-2 assay on COBAS 6000 systems agreed with paired serum results in 98.9% of cases and remained accurate at 86.7% after 9 days, supporting their use for decentralised COVID-19 serosurveillance and large-scale screening.