Brown, Lottie and Byrne, Rachel L. and Fraser, Alice and Owen, Sophie I. and Cubas-Atienzar, Ana I. and Williams, Christopher T. and Kay, Grant A. and Cuevas, Luis E. and Fitchett, Joseph R.A. and Fletcher, Tom and Garrod, Gala and Kontogianni, Konstantina and Krishna, Sanjeev and Menzies, Stefanie and Planche, Tim and Sainter, Chris and Staines, Henry M. and Turtle, Lance (2021) Self-sampling of capillary blood for SARS-CoV-2 serology. Scientific Reports, 11 (1): 7754. ISSN 2045-2322
Full text not available from this repository.Abstract
Serological testing is emerging as a powerful tool to progress our understanding of COVID-19 exposure, transmission and immune response. Large-scale testing is limited by the need for in-person blood collection by staff trained in venepuncture, and the limited sensitivity of lateral flow tests. Capillary blood self-sampling and postage to laboratories for analysis could provide a reliable alternative. Two-hundred and nine matched venous and capillary blood samples were obtained from thirty nine participants and analysed using a COVID-19 IgG ELISA to detect antibodies against SARS-CoV-2. Thirty eight out of thirty nine participants were able to self-collect an adequate sample of capillary blood (≥ 50 µl). Using plasma from venous blood collected in lithium heparin as the reference standard, matched capillary blood samples, collected in lithium heparin-treated tubes and on filter paper as dried blood spots, achieved a Cohen’s kappa coefficient of > 0.88 (near-perfect agreement, 95% CI 0.738–1.000). Storage of capillary blood at room temperature for up to 7 days post sampling did not affect concordance. Our results indicate that capillary blood self-sampling is a reliable and feasible alternative to venepuncture for serological assessment in COVID-19.