Stroke, Myocardial Infarction, and Pulmonary Embolism after Bivalent Booster
Marie-Joëlle Jabagi, Marion Bertrand, Jérémie Botton, Stéphane Le Vu, Alain Weill, Rosemary Dray‐Spira, Mahmoud Zureik
Abstract
Pulmonary Embolism after Bivalent BoosterTo the Editor: A bivalent messenger RNA vaccine targeting both the ancestral and omicron BA.4-BA.5 sublineages of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (Pfizer-BioNTech) was introduced in France in early October 2022 and recommended for booster vaccination in vulnerable populations.Between October 6 and November 9, both monovalent and bivalent vaccines were available for administration to persons who were 50 years of age or older.In January 2023, the Vaccine Safety Datalink of the Centers for Disease Control and Prevention alerted the public about a possible increased risk of ischemic stroke within the 21 days after the bivalent injection in persons 65 years of age or older. 1 We previously found no increase in the incidence of stroke, acute myocardial infarction, or pulmonary embolism after administration of the monovalent vaccine. 2,3Thus, we wanted to assess whether the risk of such events differed after receipt of the bivalent booster as compared with the monovalent booster.In this population-based study, we used comprehensive data from the French National Health Data System linked to the national coronavirus disease 2019 (Covid-19) vaccination database.All persons who were 50 years of age or older and who had received a booster dose between October 6 and November 9, 2022, were included in the study.This time window captured the only period in which both vaccines were being administered in France.During this period, the uptake of the bivalent vaccine overtook the uptake of the monovalent vaccine, with 932,583 persons receiving the bivalent vaccine and 121,362 receiving the monovalent vaccine (Fig. S1 in the Supplementary Appendix, available with the full text of this letter at NEJM.org).