1.
ssrn; 2021.
Preprint
in English
| PREPRINT-SSRN | ID: ppzbmed-10.2139.ssrn.3880967
ABSTRACT
Adults receiving heterologous prime-boost COVID-19 immunisation schedules with mRNA (Pfizer-BioNTech) or adenoviral-vector (ChAdOx1-S/nCOV-19) vaccines had higher reactogenicity rates and were more likely to seek medical attention after their second dose than homologous schedules. Reactogenicity rates were generally higher among ≤50 than >50 year-olds and in adults with prior symptomatic or confirmed COVID-19. Adults receiving heterologous schedules because of severe first-dose reactions had lower reactogenicity after the second dose following ChAdOx1-S/Pfizer-BioNTech (93.4%[90.5-98.1] vs. 48%[41.0-57.7]) but not Pfizer-BioNTech/ChAdOx1-S (91.7%[77.5-98.2] vs. 75.0%[57.8-87.9]).