ABSTRACT
Aim: Coronavirus disease 2019 antibody testing often relies on venous blood collection, which is labor-intensive, inconvenient and expensive compared with finger-stick capillary dried blood spot (DBS) collection. The purpose of our work was to determine if two commercially available anti-severe acute respiratory syndrome coronavirus 2 enzyme-linked immunosorbent assays for IgG antibodies against spike S1 subunit and nucleocapsid proteins could be validated for use with DBS. Materials & methods: Kit supplied reagents were used to extract DBS, and in-house DBS calibrators were included on every run. Results: Positive/negative concordance between DBS and serum was 100/99.3% for the spike S1 subunit assay and 100/98% for the nucleocapsid assay. Conclusion: Validation of the DBS Coronavirus disease 2019 IgG antibody assays demonstrated that serum and DBS can produce equivalent results with minimal kit modifications.
Subject(s)
COVID-19 Testing/standards , COVID-19/diagnosis , Dried Blood Spot Testing/standards , Enzyme-Linked Immunosorbent Assay/standards , SARS-CoV-2/immunology , Antibodies, Viral/chemistry , Antigens, Viral/blood , Antigens, Viral/immunology , COVID-19/blood , COVID-19/immunology , COVID-19/virology , Coronavirus Nucleocapsid Proteins/blood , Coronavirus Nucleocapsid Proteins/immunology , Female , Humans , Immunoglobulin G/chemistry , Male , Middle Aged , Phosphoproteins/blood , Phosphoproteins/immunology , Reagent Kits, Diagnostic/standards , Reproducibility of Results , Sensitivity and Specificity , Spike Glycoprotein, Coronavirus/blood , Spike Glycoprotein, Coronavirus/immunologyABSTRACT
Accurate surveillance of coronavirus disease 2019 (COVID-19) incidence requires large-scale testing of the population. Current testing methods require in-person collection of biospecimens by a healthcare worker, limiting access of individuals who do not have access to testing facilities while placing both patients and healthcare workers at risk of exposure to infection. We report the development and validation of a at-home finger-prick dried blood spot collection kit and an analysis method. We demonstrated 100% sensitivity and specificity using at-home collected specimens across the US. Such methods may facilitate the conduct of unbiased serosurveys within hard to reach populations and help reduce the sample collection burden of serological testing on both health care systems and individuals alike.