Antibodies
A 5cc whole blood sample was drawn (without anticoagulants), and serum was derived from the specimen using centrifugation (3000xg for 10 minutes). The Enzyme-linked Immunosorbent Assay (ELISA) ‎method (Pishtaz Teb SARS-CoV-2 IgM and IgG- Iran) was used to test the serum antibody levels. The test was performed ‎according to the manufacturer’s brochure. Results greater ‎than 1.1 were considered positive and those less than 0.9 as negative. Results within ‎the mentioned range were reported as borderline and the test was redone on a second, fresh serum sample to confirm the initial results.
‎The manufacture reported diagnostic specifications of the test kits: ‎
Specificity: 97.30% and Sensitivity: 79.40% for SARS-COV-2-IGM kit. ‎
Specificity: 98.30%% and sensitivity: 91.10% for SARS-COV-2-IGG kit. ‎