Longitudinal analysis of IgG levels and memory B cells following Pfizer (BNT162b2)/Moderna (mRNA-1273) vaccination

A group from University of Pennsylvania Perelman School of Medicine has reported longitudinal analysis results of IgG levels and memory B cells following Pfizer (BNT162b2)/Moderna (mRNA-1273) vaccination.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7941668/

  1. Vaccination boosts antibody levels for both SARS-CoV-2 recovered people and SARS-CoV-2 inexperienced people
  2. but, no additional boosting is observed after the second vaccine dose for SARS-CoV-2 recovered people
  3. Memory B cell responses continue to improve after the second dose for SARS-CoV-2 inexperienced people
  4. All ages benefit from vaccination, but vaccine induction of memory B cells declines with age
  5. No relationship between post-vaccine IgG levels and memory B cells in SARS-CoV-2 inexperienced people
  6. Memory B cells strongly correlate with post-vaccination IgG levels in SARS-CoV2 recovered people
  7. The importance of measuring memory B cells induced by the vaccination is emphasized

So, this means that SARS-CoV-2 recovered people do not need vaccination twice, but SARS-CoV-2 inexperienced people do need vaccination twice definitely.