Since April, more than 1,000 reports of heart inflammation have raised concerns about whether mRNA-based vaccines like those made by Pfizer and Moderna are worth the risk, despite hundreds of millions of doses administered without incident.
A new report has the latest recommendations from the CDC.
Like so much in epidemiology, it's a numbers game: The same number of doses that could cause up to 47 myocarditis cases could also prevent a projected 11,000 coronavirus cases, 560 hospitalizations and six deaths.
Myocarditis is an inflammation of the heart muscle. Researchers also included the possibility of pericarditis, an inflammation of the thin tissue surrounding the heart, in their evaluation.
Cold calculations might offer cold comfort to those most affected — males ages 12-29 receiving their second dose — but, although nearly all of the cases the CDC reviewed ended up in hospitals, most were mild and none were fatal.
What's more, at a time when no alternatives for adolescents are available, mRNA-based inoculations can reduce transmission, cut down on variants and let young people return to school and extracurricular activities.
Based on its findings, the Advisory Committee on Immunization Practices says the benefits of COVID-19 vaccination to individuals and the population in general outweigh the risks posed by myocarditis. The authors added that the risk-benefit balance shifts with age and sex, since cases occur most often among males under 30 years, and poor outcomes related to COVID-19 increase with age.
The CDC recommends doctors inform patients of myocarditis risks and symptoms, which typically include chest pain, breathing difficulties or palpitations. The agency has published guidelines for evaluation and management of the disease after mRNA vaccinations, along with considerations for those who develop myocarditis after their first shot.
The U.S. Food and Drug Administration has updated its Emergency Use Authorization fact sheets for the Pfizer-BioNTech COVID-19 (BNT162b2) vaccine and the Moderna COVID-19 (mRNA-1273)vaccine to reflect the potential for post-inoculation myocarditis or pericarditis.
