Self-collection of capillary blood using Tasso-SST devices for Anti-SARS-CoV-2 IgG antibody testing

PLoS One. 2021 Sep 2;16(9):e0255841. doi: 10.1371/journal.pone.0255841. eCollection 2021.

Abstract

Background: Efforts to minimize COVID-19 exposure during the current SARS-CoV-2 pandemic have led to limitations in access to medical care and testing. The Tasso-SST kit includes all of the components necessary for remote, capillary blood self-collection. In this study, we sought to investigate the accuracy and reliability of the Tasso-SST device as a self-collection device for measurement of SARS-CoV-2 IgG antibodies.

Methods: Capillary blood was obtained via unsupervised and supervised application of the Tasso-SST device, and venous blood was collected by standard venipuncture. Unsupervised self-collected blood samples underwent either extreme summer or winter-simulated shipping conditions prior to testing. Sera obtained by all three methods were tested concurrently using the EuroImmun anti-SARS-CoV-2 S1 IgG assay in a CLIA-certified clinical laboratory.

Results: Successful Tasso-SST capillary blood collection by unsupervised and supervised administration was completed by 93.4% and 94.5% of participants, respectively. Sera from 56 participants, 55 with documented (PCR+) COVID-19, and 33 healthy controls were then tested for anti-SARS-CoV-2 IgG antibodies. Compared to venous blood results, Tasso-SST-collected (unstressed) and the summer- and winter-stressed blood samples demonstrated Deming regression slopes of 1.00 (95% CI: 0.99-1.02), 1.00 (95% CI: 0.98-1.01), and 0.99 (95% CI: 0.97-1.01), respectively, with an overall accuracy of 98.9%.

Conclusions: Capillary blood self-collection using the Tasso-SST device had a high success rate. Moreover, excellent concordance was found for anti-SARS-CoV-2 IgG results between Tasso-SST capillary and standard venous blood-derived sera. The Tasso-SST device should enable widespread collection of capillary blood for testing without medical supervision, facilitating epidemiologic studies.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Antibodies, Viral / immunology*
  • Blood Specimen Collection / instrumentation
  • Blood Specimen Collection / methods*
  • COVID-19 / diagnosis*
  • COVID-19 / epidemiology
  • COVID-19 / virology
  • COVID-19 Testing / instrumentation
  • COVID-19 Testing / methods*
  • Female
  • Humans
  • Immunoglobulin G / immunology*
  • Male
  • Middle Aged
  • Pandemics
  • Reproducibility of Results
  • SARS-CoV-2 / immunology*
  • SARS-CoV-2 / physiology
  • Sensitivity and Specificity
  • Young Adult

Substances

  • Antibodies, Viral
  • Immunoglobulin G

Grants and funding

This study was supported by Tasso, Inc. (https://www.tassoinc.com) in the form of a grant awarded to ANH and salaries for EJW, EB and BAQ, and by University of Washington (UW) Department of Laboratory Medicine and Pathology (DLMP) (https://dlmp.uw.edu/) in the form of salaries for TH, AC, KVL, JC, SLF, MHW, ANH and CM. The specific roles of these authors are articulated in the ‘author contributions’ section. Tasso, Inc. approved the study design, conducted the shipping simulation procedures, compiled demographic information, were consulted during data analysis, and manuscript preparation, and approved the final manuscript that was submitted. They were not involved in decisions on how to analyze or present the data, or decision to publish. UW DLMP had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.