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- The CDC is investigating a very rare heart condition that some young vaccine recipients reported.
- Some people developed myocarditis, an inflammation of the heart muscle.
- The vaccine advisory committee said the figures are the same as baseline rates of the condition.
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A very small number of teenagers and young adults who have received either Pfizer or Moderna COVID-19 vaccines have reported heart problems, but the Centers for Disease Control and Prevention says it's not clear if it's related to the vaccine itself.
The CDC's vaccine safety group reported that myocarditis, an inflammation of the heart muscle, was reported in a "relatively few" number of young people a few days after they received their second dose of either of the mRNA vaccines. The condition appeared more prevalent in males than females.
The safety group said that most cases appear to be mild and they're continuing to follow up on cases.
The advisory group noted that the rate of reported myocarditis cases after COVID-19 vaccinations was not different from the baseline rate, which means there may not be a link between vaccination and the condition.
A study from last year published on the National Institute of Health site found that about 10 to 20 of every 100,000 people develop myocarditis worldwide each year, but experts said some cases may be missed and never diagnosed.
"It may simply be a coincidence that some people are developing myocarditis after vaccination," Dr. Celine Gounder, an infectious disease specialist at Bellevue Hospital Center in New York, told The New York Times. "It's more likely for something like that to happen by chance because so many people are getting vaccinated right now."
The Pfizer vaccine is the only vaccine approved for those under the age of 18. Around 4.6 million Americans between the ages of 12 and 18 have already received one dose, with more than 1.8 million being fully vaccinated, according to data from the CDC.
Experts are still encouraging young people to get vaccinated and have said the risks of severe COVID-19 or long-haul symptoms outweigh risks associated with the potentially rare side effect of myocarditis, the Times reported.
The American Academy of Pediatrics reported that more than 3.9 million children have been infected with COVID-19 so far, more than 16,000 have been hospitalized, and at least 308 have died, according to data from May 13.