Evaluation of commercial SARS-CoV-2 serological assays in Canadian public health laboratories

Stein, Derek R.; Osiowy, Carla; Gretchen, Ainsley; Thorlacius, Laurel; Fudge, Denise; Lang, Amanda; Sekirov, Inna; Morshed, Muhammad; Levett, Paul N.; Tran, Vanessa; Kus, Julianne V.; Gubbay, Jonathan; Mohan, Vandana; Charlton, Carmen; Kanji, Jamil N.; Tipples, Graham; Serhir, Bouchra; Therrien, Christian; Roger, Michel; Jiao, Lei; Zahariadis, George; Needle, Robert; Gilbert, Laura; Desnoyers, Guillaume; Garceau, Richard; Bouhtiauy, Ihssan; Longtin, Jean; El-Gabalawy, Nadia; Dibernardo, Antonia; Lindsay, L. Robbin; Drebot, Michael

The COVID-19 pandemic has led to the influx of immunoassays for the detection of antibodies towards severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) into the global market. The Canadian Public Health Laboratory Network Serology Task Force undertook a nationwide evaluation of twelve laboratory and 6 point-of-care based commercial serological assays for the detection of SARS-CoV-2 antibodies. We determined that there was considerable variability in the performance of individual tests and that an orthogonal testing algorithm should be prioritized to maximize the accuracy and comparability of results across the country. The manual enzyme immunoassays and point-of-care tests evaluated had lower specificity and increased coefficients of variation compared to automated enzyme immunoassays platforms putting into question their utility for large-scale sero-surveillance. Overall, the data presented here provide a comprehensive approach for applying accurate serological assays for longitudinal sero-surveillance and vaccine trials while informing Canadian public health policy.