CDC Reports 1,200 Cases of a Heart Inflammation Condition After Receiving Pfizer, Moderna Vaccines

Roughly 1,200 cases of a heart inflammation condition have been reported in individuals — primarily young men — after receiving the Pfizer or Moderna vaccines, according to the Centers for Disease Control and Prevention (CDC).

The government agency’s Advisory Committee on Immunization Practices is holding a meeting on Wednesday to discuss the development of myocarditis or pericarditis in young people, 16- to-24-year-olds primarily, after receiving either of the two mRNA vaccines. The vast majority of the confirmed cases have occurred after receiving the second dose in the vaccine series.

According to the CDC’s presentation slide, 267 cases of the heart inflammation condition developed after the first dose, with 827 cases developing after two doses as of June 11. The CDC categorized 132 additional cases where the dosage number is not certain.

The vast majority of the cases are developing in men under the age of 30.

According to CNBC:

Men under 30 make up the bulk of the cases, the CDC said, and most cases appear to be mild. Of the 295 people who have developed the condition and have been discharged, 79% of them have fully recovered, according to the presentation. Nine people were hospitalized, with two in intensive care as of June 11, according to the CDC.

The vast majority of vaccinated Americans opted for the non-traditional mRNA vaccines, which according to the CDC “teach our cells how to make a protein—or even just a piece of a protein—that triggers an immune response inside our bodies.”

Over 78 million people who are considered “fully vaccinated” in the U.S. opted for the two-dose Pfizer vaccine, with over 59 million receiving the two-dose Moderna. Just under 12 million have received the single does J&J.