However, serological tests are needed for screening acute disease diagnosis and screening large populations during the COVID-19 outbreak.<h4>Objectives</h4>Herein, we described the development and validation of an in-house enzyme-linked immunosorbent assay (ELISA) for detecting the levels of anti-spike-1-RBD IgM antibody (CovIgM-ELISA) in well-defined serum/plasma panel for screening and identifying subjects infected with SARS-CoV-2 in a Latin population.<h4>Method</h4>In-house CovIgM-ELISA has the format of an indirect ELISA. Here, CD40LG is linked to COVID-19.