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Risks of Emergency Department Visits, Hospitalisations, Life-Threatening Events, and Deaths After SARS/nCoV2 Vaccination in the US: An Observational Study Using National Data
23 Pages Posted: 22 Sep 2021
More...Abstract
Background: Vaccination programmes against SARS/nCoV2 have suffered setbacks and were paused in several countries due to reports of rare serious adverse events (SAEs). In this study, we analyse the real-world risks of SAEs after BNT-162b (Pfizer/BioNTech), mRNA-1273 (Moderna) and Ad26.COV2.S (Janssen) vaccination in the United States.
Methods: We analysed data from the national Vaccine Adverse Events Reporting System in the US for recipients 17 years and older, from January 13, 2021, to May 27, 2021. The crude cumulative 28-day incidence (risks) for emergency department (ED) visits, hospitalisations, life-threatening adverse events, and deaths were calculated using total number of vaccine doses administered nationwide during the study period. Incidence rate ratios (IRRs) were compared between mRNA (BNT-162b and mRNA-1273) and adenovector (Ad26.COV2.S) vaccines using generalised Poisson regression models.
Findings: During the study period, 281 million doses of SARS/nCoV2 vaccines were administered nationwide, and a total 204,442 unique patient adverse events were reported. Crude cumulative 28-day incidence per 100,000 vaccine doses for ED visits were 8·82 (95% CI 8·70–8·93) for mRNA vaccines vs. 39·85 (38·62–41·09) for adenovector vaccine; for hospitalisations 4·24 (4·16–4·32) vs. 14·10 (13·37–14·83); for life-threatening events 1·33 (1·29–1·39) vs. 5·63 (5·16–6·09); and for deaths 1·03 (0·99–1·07) vs. 2·45 (2·14–2·75). After adjustment for age and sex, there were no differences in IRR between mRNA and adenovector for hospital admissions [IRR 0·96 (0·90–1·01)], life-threatening events [IRR 1·08 (0·98–1·17)], and deaths [IRR 0·92 (0·81–1·04)].
Interpretation: Overall risks of reported serious adverse events and deaths associated with SARS/nCoV2 vaccination were low. Risks for women and young adults, were lower than for men and older (>75 years) vaccinees respectively. These results provide reassurance on the overall safety and support continued use of both adenovector and mRNA-based vaccines.
Funding Information: None.
Declaration of Interests: None of the authors have any competing interests or conflicts to declare.
Suggested Citation: Suggested Citation