Feasibility, Accuracy, and Acceptability of Self-Collected Dried Blood Spots for Hepatitis C Virus, Hepatitis B Virus, and SARS-CoV-2 Testing
Sarah S Tran, Aaron Vanderhoff, Ahreni Saunthar, Agustina Crespi, Bethany Barber, Andrew B Mendlowitz, Anne-Claude Gingras, Karen Colwill, Freda Qi, Melanie Delgado-Brand, Tony Mazzulli, John Kim, Nikolina Mizdrak, Camelia Capraru, Mia J Biondi, Jordan J FeldAbstract
Background
Screening, diagnosis, and treatment for hepatitis C and hepatitis B can be limited due to challenges in accessing in-person health care. This study explored the alternative method of dried blood spot (DBS) collection, specifically through mail-based self-collection.
Methods
A total of 388 patients were recruited by phone from the Toronto Centre for Liver Disease and the Toronto Western Family Health Team, who were seropositive for hepatitis C virus (HCV), hepatitis B virus, and/or SARS-CoV-2 or had unknown serostatus. Participants were mailed a collection kit, paper instructions/QR code for video instructions, demographic/acceptability questionnaires, a return envelope, and laboratory requisition. DBS cards and phlebotomy were tested for hepatitis B surface antigen, HCV antibody, and SARS-CoV-2 antibody. DBS results were compared against conventional phlebotomy as the gold standard.
Results
Of the 388 recruited participants, 110 completed the study by returning their DBS cards and completing conventional phlebotomy and questionnaires. For hepatitis B surface antigen, self-collection DBS testing showed 100% sensitivity and specificity, with 31 true positives and 79 true negatives. For HCV antibody, self-collection DBS testing showed 96.2% (25/26) sensitivity and 96.4% specificity (81/84), with 25 true positives, 81 true negatives, 3 false positives, and 1 false negative. SARS-CoV-2 testing also showed 100% sensitivity and specificity, with 108 true positives and 2 true negatives. Acceptability was high with 78.3% (101/129) participants rating the process easy or very easy.
Conclusions
Mail-based self-collected DBS enables remote testing by allowing nonmedically trained individuals to reliably collect their own samples. High concordance and acceptability indicate that this method is viable for addressing health care access challenges, particularly in populations motivated to seek testing.