Abstract
Two mRNA COVID-19 vaccines (mRNA-1273, Moderna; and BNT162b2, Pfizer-BioNTech) and one viral vector vaccine (JNJ-78436735, Janssen/Johnson and Johnson) are authorized in the US to hinder COVID-19 infections. We analyzed severe and common adverse events in response to COVID-19 vaccines using real-world, Vaccine Adverse Effect Reporting System (VAERS) data. From 14 December 2020 to 30 September 2021, 481,172 (50.7 ± 17.5 years, males 27.89%, 12.35 per 100,000 people) individuals reported adverse events (AEs). The median time to severe AEs was 2 days after injection. The risk of severe AEs following the one viral vector vaccine (OR = 1.044, 95% CI = 1.005–1.086) was significantly higher than that after the two mRNA vaccines, and the risk among males (OR = 1.374, 95% CI = 1.342–1.406) was higher than among females, except for anaphylaxis. For common AEs, however, the risk to males (OR = 0.621, 95% CI = 0.612–0.63) was lower than to females. In conclusion, we provided medical insight and clinical guidance about vaccine types by characterizing AEs using real-world data. In particular, COVID-19 mRNA vaccines are safer than viral vector vaccines with regard to coagulation disorders, whereas inflammation-related AEs are lower in the viral vaccine. The risk–benefit ratio of vaccines should be carefully considered, and close monitoring and management of severe AEs is needed.
Highlights
The risk of severe adverse events (AEs) was high after the viral vector vaccine with regard to death, Guillain–Barré syndrome, acute respiratory distress syndrome, and coagulation disorders, which might have implications for monitoring strategies
For breakthrough COVID-19 infections following the two messenger RNA (mRNA) vaccines, the odds ratio of females to males was low, and the odds ratio of mRNA-1273 compared to BNT162b2 was 0.5694, indicating that mRNA-1273 had a lower risk than BNT162b2
We found that the odds ratio (OR) of mRNA-1273 for severe AEs such as Guillain–Barré syndrome (GBS), MT, DVT, and LP were significantly low compared to BNT162b2
Summary
Safe and effective vaccines against SARS-CoV-2 are needed to stop the pandemic. Two 2-dose messenger RNA (mRNA) vaccines (mRNA-1273, Moderna; and BNT162b2, Pfizer-BioNTech) and one 1-dose viral vector vaccine (JNJ-78436735, Janssen/Johnson and Johnson) against SARS-CoV-2 have been authorized in the US to prevent serious COVID-19 infections [2,3]. The rapid development of COVID-19 vaccines and mass vaccination have provided effective protection against COVID-19, systematic trends in unexpected serious adverse events (AEs) associated with the vaccines have not been identified. COVID-19 vaccinations and systematically classified AEs, including death. The CDC and FDA continue to monitor product safety for use by collecting and analyzing spontaneous reports of AEs that occur in people following vaccination [6]. This study evaluates AEs to provide accurate post-vaccination safety information by comparing the two mRNA vaccines and one viral vector vaccine
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