To put vaccine risk in perspective, consider the most frequent serious adverse event in any demographic: the rate of myocarditis in younger males. According to available
evidence, if Fenway park were filled to capacity with some 37,000 fully vaccinated men aged 18 to 24, just two might experience transient myocarditis. By contrast, if all 37,000 of these men were unvaccinated and infected with the delta variant, many more would experience a diverse array of clinical outcomes, including extended periods in hospital, virus-induced myocardial injury, and diverse post-acute health complications described as “long COVID.” In other words, the sum of the diverse risks associated with vaccination are dwarfed by the diverse and incompletely understood risks posed by the novel coronavirus.