Early-stage neutralizing antibody level associated with the re-positive risk of Omicron SARS-CoV-2 RNA in patients recovered from COVID-19

Abstract

Post-discharge re-positivity of Omicron SARS-CoV-2 is challenging for the sufficient control of this pandemic. However, there are few studies about the risk of re-positivity. We aimed to explore the association of neutralizing antibodies (nAbs, AU/mL) with the incidence of re-positivity among patients recovered from COVID-19. A retrospective cohort study selected 318 Omicron-infected patients was conducted in China between December 2021 and April 2022. The peak value of nAb levels (nAb-peak) within 14 days of disease onset was defined as the baseline and was mainly used for the subsequent analyses. In the unadjusted, minimally adjusted, fully adjusted, and additionally adjusted for IgG models, a per-standard deviation (SD) increase in the nAb-peak values was significantly associated with a 59 %, 59 %, 50 %, and 75 % decreased risk of Omicron SARS-CoV-2 re-positivity during post-discharge surveillance, respectively. Stratified analyses showed no significant changes in the relationship between nAbs and re-positivity. Our study suggested that the increase in baseline nAb levels independently associated with a low risk of re-positivity in patients recovered from COVID-19.

Keywords: COVID-19; Neutralizing antibody; Omicron; Re-positivity; SARS-CoV-2.