Development and Implementation of Dried Blood Spot-Based COVID-19 Serological Assays for Epidemiologic Studies
Marcus P. Wong, Michelle Meas, Cameron Adams, Samantha Hernandez, Valerie Green, Magelda Montoya, Brett M. Hirsch, Mary Horton, Hong Quach, Diana Quach, Xiaorong Shao, Indro Fedrigo, Alexandria Zermeno, Julia Huffaker, Raymond Montes, Alicia Madden, Sherri Cyrus, D. Gordon McDowell, Phillip Williamson, Paul Contestable, Mars Stone, Joséfina Coloma, Michael P. Busch, Lisa F. Barcellos, Eva Harris
Abstract
Estimation of community-level antibody responses to SARS-CoV-2 from infection or vaccination is critical to inform public health responses. Traditional studies of antibodies rely on collection of blood via venipuncture, an invasive procedure not amenable to pandemic-related social-distancing measures. Dried blood spots (DBS) are an alternative to venipuncture, since they can be self-collected by study participants at home and do not require refrigeration for shipment or storage. However, DBS-based assays to measure antibody levels to SARS-CoV-2 have not been widely utilized. Here, we show that DBS are comparable to blood as a sampling method for antibody responses to SARS-CoV-2 infection and vaccination over time measured using four distinct serological assays. The DBS format enabled antibody surveillance in a longitudinal cohort where study participants self-collected samples, ensuring the participants' safety during an ongoing pandemic. Our work demonstrates that DBS are an excellent sampling method for measuring antibody responses whenever venipuncture is impractical.