Chapter 8 252 Figure 4. Rate of spike- and RBD-binding IgG decay after illness onset, by PASC status at 3 months after illness onset Figures show results of a Bayesian hierarchical linear regression of the log response variable (Y) against time since symptom onset (t), pooling decay rates across participants. Each connected line represents one study participants, coloured by COVID-19 severity. PASC groups were defined as to whether the participant continued to experience one or more symptoms at 3 months after illness onset. Estimated median half-life and the corresponding 95% credible interval (95CrI) of spike- and RBD-binding IgG levels are computed from the median (black line) and posterior distribution (grey region) of regressed lines. PASC = Post-acute sequelae of COVID-19. DISCUSSION We assessed the effect of SARS-CoV-2 vaccination on symptoms PASC within a wellcharacterised prospective cohort of participants with PASC who had mild to critical COVID-19. We found no clear evidence of a beneficial effect of vaccination on PASC symptoms. These findings were corroborated by serological data, in which there was no overall difference in early neutralising antibody titers between participants with and without PASC at 3 months after illness onset, nor in antibody decay up to 9 months after illness onset. Despite initial optimism arising from studies reporting improvement or even full recovery of PASC symptoms following SARS-CoV-2 vaccination, evidence to date is conflicting. Our study supports the evidence base that points to a lack of effect: we found no difference in the mean number of PASC symptoms reported up to 3 months after first vaccination
RkJQdWJsaXNoZXIy MTk4NDMw