What are the absolute rates of myocarditis and stroke after COVID‑19 infection versus vaccination specifically in adults aged 65–79 and 80+?
Executive summary
Available large studies and meta-analyses consistently show that COVID‑19 infection carries a higher absolute risk of myocarditis than COVID‑19 vaccination and that vaccination does not increase, and may lower, the risk of stroke; however, the reviewed sources do not provide robust, directly reported absolute rates broken down specifically for adults aged 65–79 and 80+, so conclusions for those age bands must be qualified by gaps in the published breakdowns [1] [2] [3] [4].
1. Myocarditis: the headline numbers and direct comparisons
Multiple large analyses find myocarditis is rare overall after vaccination and more common after SARS‑CoV‑2 infection; a systematic review found the relative risk for myocarditis was roughly seven times higher following infection than following vaccination (infection RR ≈15 versus vaccine RR ≈2) and reported low overall hospitalization and death among myocarditis cases (1.07% hospitalized; 0.015% died among diagnosed cases) [1] [5]. Population studies in England recorded 617 myocarditis events in the 1–28 day window after any vaccine dose—about 0.001% of vaccinated people—and 195 hospitalizations or deaths with myocarditis in the 1–28 days after a positive SARS‑CoV‑2 test—about 0.003% of infected people—again indicating higher absolute risk after infection in these cohorts [2]. Other syntheses report infection‑associated myocarditis rates on the order of a few cases per 100,000 infected people (for example, 4.42 per 100,000 in one analysis of ≥16‑year‑olds), while vaccine‑associated myocarditis—though present and concentrated in younger males—produces only single‑digit additional cases per 100,000 doses in most estimates [4] [6] [7].
2. Stroke: infection raises risk; vaccination does not
The literature reviewed ties COVID‑19 infection to increased short‑ and longer‑term risks of ischemic stroke and other major cardiovascular events, and several cohort studies report higher rates of myocardial infarction and ischemic stroke among unvaccinated or post‑COVID cohorts compared with vaccinated individuals [8] [9]. Nationwide analyses in Sweden and other large cohorts found no increased risk of stroke after vaccination and in many instances observed lower risks of several severe cardiovascular outcomes—attributed to vaccination’s prevention of infection and severe COVID—while also reproducing the small short‑term increase in myocarditis after mRNA doses [3] [9].
3. What the sources do and do not deliver for the 65–79 and 80+ age bands
None of the supplied sources presents a clean, directly reported absolute rate table that isolates myocarditis and stroke incidence specifically for adults aged 65–79 and 80+ in parallel after infection versus after vaccination; most report aggregate adult rates, age‑stratified signals emphasizing younger age groups, or relative risks rather than the exact per‑100,000 incidence for those two elderly bands [2] [1] [7]. Some population studies note myocarditis is concentrated in younger males and that elderly populations have much lower vaccine‑associated myocarditis rates and, conversely, bear the largest absolute stroke and severe‑outcome burden from infection—yet the precise absolute rates for 65–79 and 80+ after infection versus vaccination are not enumerated in the provided reporting [6] [9] [4]. The National Academies and major journal reviews emphasize that older adults face higher baseline cardiovascular risk and that COVID‑19 infection increases cardiovascular events, but they stop short of publishing the specific per‑100,000 post‑infection and post‑vaccine myocarditis/stroke numbers for the requested age strata in the sources given [10] [11].
4. Translation for risk assessment and remaining uncertainties
Taken together, the best-supported, directly cited message is that COVID‑19 infection confers a higher absolute risk of myocarditis than vaccination in adults overall and increases stroke risk, while vaccination carries only a small absolute myocarditis risk concentrated in younger males and is not associated with increased stroke risk in older adults—and may reduce stroke through prevention of infection [1] [2] [3]. That conclusion is robust at the population level but, because the supplied studies do not publish the requested clean absolute incidence rates specifically for ages 65–79 and 80+, any precise per‑100,000 comparison for those bands cannot be stated from these sources alone; targeted age‑stratified incidence tables or raw data from national registries would be needed to produce the exact numbers requested [2] [4] [7].