Antibody Responses to SARS-CoV-2 at 8 Weeks Postinfection in Asymptomatic Patients

Abstract

We compared levels of severe acute respiratory syndrome coronavirus 2 neutralizing antibodies in recovery plasma from 7 completely asymptomatic coronavirus disease patients with those in symptomatic patients in South Korea. We found that serologic diagnostic testing was positive for 71% (5/7) of completely asymptomatic patients, but neutralizing antibody response occurred in all 7 patients.

Keywords: 2019 novel coronavirus disease; COVID-19; SARS; SARS-CoV-2; asymptomatic; coronavirus; coronavirus disease; neutralizing antibody; respiratory infections; severe acute respiratory syndrome coronavirus 2; viruses; zoonoses.

Figure

Antibody response against severe acute respiratory syndrome coronavirus 2 at 8 weeks postinfection among patients and controls in South Korea. A) Serologic diagnostic test (ELISA) results. OD ratio indicates the ratio of the extinction of the patient sample over the extinction of the calibrator. B) Neutralization assay results. For each patient type, an outlined symbol indicates a negative test result, gray symbol a borderline result, and black symbol a positive result, as tested according to manufacturer recommendation. Bars represent mean values and SE. From each patient group other than the completely asymptomatic group, 3–4 patients were randomly selected for neutralization assay. The controls included 1 healthy volunteer and 2 patients with MERS. Ab, antibody; MERS, Middle East respiratory syndrome; OD, optical density.