Waning Antibodies

Antibody titres (blood levels) are an imperfect measure of infection risk. Post-vaccination, the body activates other defence mechanisms like the T and B lymphocytes. It is, however, concerning that the University College of London (UCL) Virus Watch Study found substantial declines in antibodies, within weeks of a second Covid vaccination jab (https://www.theguardian.com/world/2021/jul/22/uk-scientists-back-covid-boosters-as-study-finds-post-jab-falls-in-antibodies). The UCL study monitored antibody titres in more than 600 subjects in their 50s and 60s. Subjects had had 2 doses of either the Oxford/AstraZeneca or the Pfizer/BioNTech vaccine. Differences were noted between the levels of antibodies generated by the two vaccines. More importantly, declines in antibody levels were evident, as early as 6 weeks after the 2nd shot in both cases. In some subjects, titres fell by more than 50% over a 10 week period. The declines in antibodies might be more marked for subjects in their 70s, 80s and 90s (they have 'weaker' immune systems). The scientists advocate Covid booster doses in the Autumn (Fall). No decision has yet been taken on this. Others maintain it is more important to get unvaccinated people across the planet protected.