Protection against symptomatic SARS-CoV-2 infection conferred by the Pfizer-BioNTech Original/BA.4-5 bivalent vaccine compared to the mRNA Original monovalent vaccines – A matched cohort study in France
Vincent Auvigne, Cynthia Tamandjou, Justine Schaeffer, Sophie Vaux, Isabelle Parent du Châtelet
Abstract
This cohort study evaluated the protection against symptomatic Omicron BA.5 infection conferred by the Pfizer-BioNTech Original/BA.4-5 bivalent vaccine compared to mRNA Original monovalent vaccines (Pfizer- BioNTech or Moderna). Individuals of ≥60 years old, who received a booster dose between 03/10/2022 and 06/11/2022, when both bivalent and monovalent vaccines were used in France, were included and matched according to the type of booster vaccine received. The outcome of interest was a positive SARS-CoV-2 RT-PCR or antigenic test associated to self-reported symptoms, ≥ seven days after receiving the booster dose. Data were analysed with a Cox Proportional-Hazards model adjusted for the presence of previous infection, age, sex, and the presence of medium risk comorbidities. A total of 136,852 individuals were included and followed for a median period of 77 days. The bivalent vaccine conferred an additional protection of 8 % [95 % CI: 0 %-16 %, p = 0.045] against symptomatic Omicron BA.5infection compared to the monovalent vaccines.