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Delivery of Modified mRNA in a Myocardial Infarction Mouse Model
Published on: June 11, 2020
Risk of myocarditis after three doses of COVID-19 mRNA vaccines in the United States, 2020-2022: A self-controlled
Daoyuan Lai1, Dickson Lim1, Junfeng Lu2
1Department of Statistics and Actuarial Science, Faculty of Science, The University of Hong Kong, Hong Kong SAR, China.
Aim:
Myocarditis is a recognized safety concern following COVID-19 mRNA vaccination. However, there is limited research quantifying the risk associated with the third dose or comparing the risk between the three doses. The US Vaccine Adverse Event Reporting System (VAERS) is a passive surveillance system that monitors rare adverse events after US-licensed vaccination. However, studies analyzing VAERS data have often faced criticism for underreporting cases and lacking a control group to assess the increase in baseline risk.
Methods:
The temporal association between myocarditis onset and COVID-19 vaccination was studied. To overcome limitations, a novel modified self-controlled case series method was employed, explicitly modeling the case reporting process in VAERS data.
Results:
We found an increased risk of myocarditis during the 1- to 3-day period following the second and third doses of both the BNT162b2 vaccine and the mRNA-1273 vaccine. Following the second dose, the relative incidence (RI) was 4.89 (95% confidence interval (CI), 2.39-10.08) for the BNT162b2 vaccine and 2.86 (95% CI: 1.18-7.03) for the mRNA-1273 vaccine. Similarly, following the third dose, the RI was 9.04 (95% CI: 2.79-40.99) for the BNT162b2 vaccine and 4.71 (95% CI: 1.42-19.09) for the mRNA-1273 vaccine. No significant increase in risk was observed during other periods. Notably, our analysis also identified a similar increased risk of myocarditis among individuals aged below 30.
Conclusions:
These findings raise safety concerns regarding COVID-19 mRNA vaccines, provide insights into the quantification of myocarditis risk at different postvaccination periods, and offer a novel approach to interpreting passive surveillance system data.
Insights
COVID-19 mRNA vaccines show an increased risk of myocarditis after the second and third doses, particularly in individuals under 30. This study quantifies the risk using a novel method for analyzing vaccine safety data.
Area of Science:
- Cardiology
- Immunology
- Vaccinology
Background:
- Myocarditis is a known safety concern associated with COVID-19 mRNA vaccines.
- Previous research has limited data on the risk after the third dose and comparative risks across doses.
- The Vaccine Adverse Event Reporting System (VAERS) is a valuable tool but has limitations like underreporting and lack of control groups.
Purpose of the Study:
- To quantify the risk of myocarditis following different doses of COVID-19 mRNA vaccines.
- To compare the risk of myocarditis between the second and third doses.
- To address limitations of passive surveillance data using a novel analytical approach.
Main Methods:
- A modified self-controlled case series method was applied to VAERS data.
- The study analyzed the temporal association between vaccination and myocarditis onset.
- The case reporting process within VAERS was explicitly modeled to improve data interpretation.
Main Results:
- An elevated risk of myocarditis was observed within 1-3 days post-second and third doses of both BNT162b2 and mRNA-1273 vaccines.
- Relative incidence (RI) for the second dose was 4.89 (BNT162b2) and 2.86 (mRNA-1273).
- RI for the third dose was 9.04 (BNT162b2) and 4.71 (mRNA-1273), with a similar increased risk noted in individuals under 30.
Conclusions:
- Findings indicate safety concerns regarding COVID-19 mRNA vaccines and myocarditis risk.
- The study provides quantitative insights into myocarditis risk at various postvaccination times.
- A novel method for analyzing passive surveillance data was successfully developed and applied.
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