What is the incidence of myocarditis/pericarditis and new onset cardiac symptoms following smallpox and influenza vaccination?
Active safety surveillance is necessary to accurately capture the incidence of myocarditis and pericarditis following smallpox vaccination, which is underestimated by passive surveillance.
Passive surveillance significantly underestimates the true incidence of myocarditis/pericarditis after smallpox immunization. Evidence of subclinical transient cardiac muscle injury post-vaccinia immunization is a finding that requires further study to include long-term outcomes surveillance. Active safety surveillance is needed to identify adverse events that are not well understood or previously recognized.
Engler et al. (Fri,) studied this question.