Omicron variants escape the persistent SARS-CoV-2-specific antibody response in 2-year COVID-19 convalescents regardless of vaccination

Emerg Microbes Infect. 2023 Dec;12(1):2151381. doi: 10.1080/22221751.2022.2151381.


With the ongoing COVID-19 pandemic and the emergence of various SARS-CoV-2 variants, a comprehensive evaluation of long-term efficacy of antibody response in convalescent individuals is urgently needed. Several longitudinal studies had reported the antibody dynamics after SARS-CoV-2 acute infection, but the follow-up was mostly limited to 1 year or 18 months at the maximum. In this study, we investigated the durability, potency, and susceptibility to immune evasion of SARS-CoV-2-specific antibody in COVID-19 convalescents for 2 years after discharge. These results showed the persistent antibody-dependent immunity could protect against the WT and Delta variant to some extent. However, the Omicron variants (BA.1, BA.2, and BA.4/5) largely escaped this preexisting immunity in recovered individuals. Furthermore, we revealed that inactivated vaccines (BBIBP-CorV, CoronaVac, or KCONVAC) could improve the plasma neutralization and help to maintain the broadly neutralizing antibodies at a certain level. Notably, with the time-dependent decline of antibody, 1-dose or 2-dose vaccination strategy seemed not to be enough to provide immune protection against the emerging variants. Overall, these results facilitated our understanding of SARS-CoV-2-induced antibody memory, contributing to the development of immunization strategy against SARS-CoV-2 variants for such a large number of COVID-19 survivors.

Keywords: 2 years after discharge; COVID-19 convalescent; Omicron variants; SARS-CoV-2; antibody response; inactivated vaccines.

MeSH terms

  • Antibodies, Neutralizing
  • Antibodies, Viral
  • Antibody Formation
  • COVID-19* / prevention & control
  • Humans
  • Pandemics
  • SARS-CoV-2* / genetics
  • Vaccination


  • sinovac COVID-19 vaccine
  • BIBP COVID-19 vaccine
  • Antibodies, Viral
  • Antibodies, Neutralizing

Supplementary concepts

  • SARS-CoV-2 variants

Grants and funding

This work was supported by the National Science Fund for Distinguished Young Scholars [grant number 82025022], the National Natural Science Foundation of China [grant numbers 92169204, 82002140, 82171752, 82101861], the National Key Plan for Scientific Research and Development of China [grant number 2021YFC0864500], the Guangdong Basic and Applied Basic Research Foundation [grant numbers 2021B1515020034, 2019A1515011197, 2021A1515011009, 2020A1515110656], the Shenzhen Science and Technology Program [grant numbers RCYX20200714114700046, RCBS20210706092345028], the Science and Technology Innovation Committee of Shenzhen Municipality [grant numbers JSGG20220226085550001, JSGG20200207155251653, JSGG20200807171401008, JSGG20210901145200002, KQTD20200909113758004], and the Shenzhen Natural Science Foundation [grant numbers JCYJ20190809115617365, JCYJ20210324115611032, JCYJ20220530163405012].