Testing is key to slowing the spread of SARS-CoV-2 infections. On March 18, 2020, Florian Krammer and his group at the Icahn School of Medicine at Mt. Sinai reported on the development of an ELISA-based serology assay to test for the presence of antibodies against the SARS-CoV-2 spike protein in blood samples from patients with COVID-19. Each of three patients tested showed reactivity against recombinant spike protein in the ELISA assay–some as early as three days after symptom onset–indicating that this test can be used to determine whether an individual is or once was infected with SARS-CoV-2.
