Fig. 1. Sensitivity of the ARCHITECT^® SARS-CoV-2 IgG assay for COVID-19 diagnosis. The SARS-CoV-2 IgG index is plotted according to the number of days after symptom onset for 206 samples collected from 70 confirmed COVID-19 cases. *Samples collected from the same patient (case 111) on days 18 and 19 and a sample collected on day 20 were positive in the IgG assay (index value: 1.52). †Sample collected from a patient (case M42) with mild symptoms at 22 days after cough onset and a nasopharyngeal swab obtained at the same time tested positive by the SARS-CoV-2 RT-PCR assay. The dashed line indicates the IgG assay cutoff value (index=1.40).
Abbreviations: SARS-CoV-2, severe acute respiratory syndrome coronavirus 2; COVID-19, Coronavirus disease 2019; RT-PCR, reverse transcription-PCR.

Ann Lab Med 2021;41:568~576 https://doi.org/10.3343/alm.2021.41.6.568