Longitudinal neutralizing antibody responses after SARS-CoV-2 infection: A convalescent cohort study in Taiwan

Yen Fang Huang, Fang Chi Hsu, Jiunn Jong Wu*, Yi Ling Lin*, Ming Tsan Liu*, Chin Hui Yang, Hsu Sung Kuo, Yen-Ju Chen, Chien Yu Cheng, His Hsun Lin, Chun Che Liao, Chih Shin Chang, Jian Jong Liang, Wen Yueh Cheng, Jason C. Huang, Cheng Pin Chen, Shu Hsing Cheng, Yi Chun Lin, Shung Haur Yang, Yiing Jenq Chou

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

1 Scopus citations


Background: Understanding the neutralizing antibody (NAb) titer against COVID-19 over time is important to provide information for vaccine implementation. The longitudinal NAb titer over one year after SARS-CoV-2 infection is still unclear. The purposes of this study are to evaluate the duration of the neutralizing NAb titers in COVID-19 convalescents and factors associated with the titer positive duration. Methods: A cohort study followed COVID-19 individuals diagnosed between 2020 and 2021 May 15th from the COVID-19 database from the Taiwan Centers for Disease Control. We analyzed NAb titers from convalescent SARS-CoV-2 individuals. We used generalized estimating equations (GEE) and a Cox regression model to summarize the factors associated with NAb titers against COVID-19 decaying in the vaccine-free population. Results: A total of 203 convalescent subjects with 297 analytic samples were followed for a period of up to 588 days. Our study suggests that convalescent COVID-19 in individuals after more than a year and four months pertains to only 25% of positive titers. The GEE model indicates that longer follow-up duration was associated with a significantly lower NAb titer. The Cox regression model indicated the disease severity with advanced condition was associated with maintaining NAb titers (adjusted hazard ratio: 2.01, 95% CI: 1.11–3.63) and that smoking was also associated with higher risk of negative NAb titers (adjusted hazard ratio: 0.55, 95% CI: 0.33–0.92). Conclusions: Neutralizing antibody titers diminished after more than a year. The antibody titer response against SARS-CoV-2 in naturally convalescent individuals provides a reference for vaccinations.

Original languageEnglish
JournalJournal of Microbiology, Immunology and Infection
StateAccepted/In press - 2023


  • COVID-19
  • Disease severity
  • Neutralizing antibody titer
  • SARS-CoV-2


Dive into the research topics of 'Longitudinal neutralizing antibody responses after SARS-CoV-2 infection: A convalescent cohort study in Taiwan'. Together they form a unique fingerprint.

Cite this