Immune response following infection with SARS-CoV-2 and other coronaviruses: A rapid review

Rev Med Virol. 2021 Mar;31(2):e2162. doi: 10.1002/rmv.2162. Epub 2020 Sep 23.


In this review, we systematically searched and summarized the evidence on the immune response and reinfection rate following SARS-CoV-2 infection. We also retrieved studies on SARS-CoV and MERS-CoV to assess the long-term duration of antibody responses. A protocol based on Cochrane rapid review methodology was adhered to and databases were searched from 1/1/2000 until 26/5/2020. Of 4744 citations retrieved, 102 studies met our inclusion criteria. Seventy-four studies were retrieved on SARS-CoV-2. While the rate and timing of IgM and IgG seroconversion were inconsistent across studies, most seroconverted for IgG within 2 weeks and 100% (N = 62) within 4 weeks. IgG was still detected at the end of follow-up (49-65 days) in all patients (N = 24). Neutralizing antibodies were detected in 92%-100% of patients (up to 53 days). It is not clear if reinfection with SARS-CoV-2 is possible, with studies more suggestive of intermittent detection of residual RNA. Twenty-five studies were retrieved on SARS-CoV. In general, SARS-CoV-specific IgG was maintained for 1-2 years post-infection and declined thereafter, although one study detected IgG up to 12 years post-infection. Neutralizing antibodies were detected up to 17 years in another study. Three studies on MERS-CoV reported that IgG may be detected up to 2 years. In conclusion, limited early data suggest that most patients seroconvert for SARS-CoV-2-specific IgG within 2 weeks. While the long-term duration of antibody responses is unknown, evidence from SARS-CoV studies suggest SARS-CoV-specific IgG is sustained for 1-2 years and declines thereafter.

Keywords: COVID-19; MERS-CoV; SARS-CoV; SARS-CoV-2; seasonal coronaviruses.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Antibodies, Neutralizing / immunology
  • Antibodies, Viral / immunology
  • COVID-19 / immunology*
  • Coronavirus / immunology*
  • Coronavirus Infections / immunology*
  • Humans
  • Immunity / immunology*
  • Immunoglobulin G / immunology
  • Immunoglobulin M / immunology
  • SARS-CoV-2 / immunology*


  • Antibodies, Neutralizing
  • Antibodies, Viral
  • Immunoglobulin G
  • Immunoglobulin M