COVID-19 mRNA Vaccines Are Generally Safe in the Short Term: A Vaccine Vigilance Real-World Study Says.

Gang Chen,Xiaolin Li,Yangzhong Zhou,Meixing Sun,Xuemei Li,Bin Zhao,Meifang Yin

doi:10.3389/fimmu.2021.669010

Abstract

BackgroundThe prophylactic vaccination of COVID-19 mRNA vaccines is the first large-scale application of this kind in the human world. Over 1.8 million doses of the COVID-19 vaccine had been administered in the US until December 2020, and around 0.2% submitted AE reports to the Vaccine Adverse Event Reporting System (VAERS). This study aimed to evaluate the AEs following immunization (AEFIs) and analyze the potential associations based on the information from the VAERS database.MethodsWe searched the VAERS database recorded AEFIs after COVID-19 vaccines in December 2020. After data mapping, we summarized demographic and clinical features of reported cases. Fisher exact test was used to comparing the clinical characteristics among AE groups with an anaphylactic response, concerning neurological disorders and death.ResultsVAERS reported 3,908 AEFIs of COVID-19 vaccines in December 2020. Most (79.68%) were reported after the first dose of the vaccine. Among the reported cases, we found that general disorders (48.80%), nervous system disorders (46.39%), and gastrointestinal disorders (25.54%) were the most common AEFIs. The allergy history was more frequent in vaccine recipients with anaphylactic reactions than those without (64.91% vs. 49.62%, OR = 1.88, P <0.017). History of anxiety or depression was more common in subjects reporting severe neurological AEFIs than those reporting other AEFIs (18.37% vs. 7.85%, OR = 2.64, P <0.017). Cases reporting death were significantly older (79.36 ± 10.41-year-old vs. 42.64 ± 12.55-year-old, P <0.01, 95% CI 29.30–44.15) and more likely experienced hypertension (50.00% vs. 11.42%, OR = 7.76, P <0.01) and neurological disorders (50.00% vs. 5.36%, OR = 17.65, P <0.01) than other vaccine recipients. The outpatient and emergency room visit rates were 11.92 and 22.42% for AEFIs, and 2.53% of cases needed hospitalization.ConclusionAEFIs of COVID-19 mRNA vaccines were generally non-severe local or systemic reactions. A prior allergy history is the risk factor for anaphylaxis, while a history of anxiety may link with severe neurological AEs. Such vaccine recipients need further evaluation and monitor.

Highlights

The prophylactic vaccination of COVID-19 messenger RNA (mRNA) vaccines is the first largescale application of this kind in the human world
Until December 2020, more than 1.8 million doses of the COVID-19 mRNA vaccine had been administered in the United States (US), and around 0.2% of adverse event (AE) reports had been submitted to the Vaccine Adverse Event Reporting System (VAERS) [7]; the reported cases were fairly sufficient to conduct certain informative analyses
Over 95% of the AE cases were reported from December 11th to December 30th, 2020, coinciding with the period when vaccines were being applied to the large-scale population

Summary

Introduction

The prophylactic vaccination of COVID-19 mRNA vaccines is the first largescale application of this kind in the human world. Over 1.8 million doses of the COVID-19 vaccine had been administered in the US until December 2020, and around 0.2% submitted AE reports to the Vaccine Adverse Event Reporting System (VAERS). Other than traditional whole-pathogen vaccines, PfizerBioNTech and Moderna adopted new generation technology and commercialized messenger RNA (mRNA) vaccines. Such vector-based vaccines only incorporate specific antigens from the pathogen, namely the spike protein fragment of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Vector-based vaccines process better safety profiles [3]; both BNT162b2 and mRNA-1273 phase 3 randomized controlled trials (RCTs) have demonstrated the low incidence (0.5–0.6%) of serious adverse events (AEs) in mRNA vaccine groups [4, 5]. Most of the AEs reported by the mRNA vaccine recipients were self-limited local and systemic reactions, such as injection site pain (71–84%), fatigue (33–51%), and headache (37– 39%) [4, 5]

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