Background: Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is generally diagnosed by reverse transcription (RT)-PCR or serological assays. The SARS-CoV-2 viral load decreases a few days after symptom onset. Thus, the RT-PCR sensitivity peaks at three days after symptom onset (approximately 80%). We evaluated the performance of the ARCHITECTR SARS-CoV-2 IgG assay (henceforth termed IgG assay;Abbott Laboratories, Lake County, IL, USA), and the combination of RT-PCR and the IgG assay for COVID-19 diagnosis.
Combination of a SARS-CoV-2 IgG assay and RT-PCR for improved COVID-19 diagnosis