COVID-19 vaccine update: vaccine effectiveness, SARS-CoV-2 variants, boosters, adverse effects, and immune correlates of protection

J Biomed Sci. 2022 Oct 15;29(1):82. doi: 10.1186/s12929-022-00853-8.


Coronavirus Disease 2019 (COVID-19) has been the most severe public health challenge in this century. Two years after its emergence, the rapid development and deployment of effective COVID-19 vaccines have successfully controlled this pandemic and greatly reduced the risk of severe illness and death associated with COVID-19. However, due to its ability to rapidly evolve, the SARS-CoV-2 virus may never be eradicated, and there are many important new topics to work on if we need to live with this virus for a long time. To this end, we hope to provide essential knowledge for researchers who work on the improvement of future COVID-19 vaccines. In this review, we provided an up-to-date summary for current COVID-19 vaccines, discussed the biological basis and clinical impact of SARS-CoV-2 variants and subvariants, and analyzed the effectiveness of various vaccine booster regimens against different SARS-CoV-2 strains. Additionally, we reviewed potential mechanisms of vaccine-induced severe adverse events, summarized current studies regarding immune correlates of protection, and finally, discussed the development of next-generation vaccines.

Keywords: COVID-19; Immunity; SARS-CoV-2; Vaccine; Variant.

Publication types

  • Review

MeSH terms

  • COVID-19 Vaccines / adverse effects
  • COVID-19* / prevention & control
  • Humans
  • SARS-CoV-2 / genetics
  • Vaccine Efficacy
  • Viral Vaccines*


  • COVID-19 Vaccines
  • Viral Vaccines

Supplementary concepts

  • SARS-CoV-2 variants