Assis et al. developed a SARS-COV-2 antigen to serve as a diagnostic tool, an epidemiologic tool to estimate the disease burden of COVID-19 more accurately, and a research tool to correlate antibody responses with clinical outcomes. This microarray was printed with 61 antigens associated with SARS-CoV-2, SARS-CoV, MERS-CoV, common cold coronaviruses, and multiple other respiratory infection antigens that cause flu-like symptoms. The study determined the optimal binding antibody assay to discriminate SARS-CoV-2 convalescent sera from pre-pandemic sera contained the S2 and NP antigens for IgG (specificity = 1, sensitivity = 0.944) and the S1, S2, and NP antigens for IgA (specificity = 0.895, sensitivity = 0.944). Larger combinations of antigens were associated with decreased predictive power. The serodiagnosis performance of the assembled panel was validated as early as 7 days post symptom onset. This platform also revealed cross-reactivity of antibodies that gives insight into SARS-CoV-2 pathology and vaccine development.