The theme of myocarditis and pericarditis following mRNA vaccination emerged in today’s Vaccines and Related Biological Products Advisory Committee meeting, which reviewed preliminary safety data of Pfizer-BioNTech vaccine in children aged 12 to 15. The risk, however, appears to be small.
As of May 31, there were 116 reports of myocarditis or pericarditis after the first dose of Pfizer-BioNTech vaccine. There were 100 for the first dose of Moderna vaccine. The problem, however, appears to be more common after the second dose. The government has collected 372 reports of myocarditis or pericarditis after the second dose of Pfizer-BioNTech vaccine and 201 for the Moderna vaccine.
Early data suggests a connection between the mRNA vaccines and myocarditis and pericarditis. Out of 2.3 million doses administered to 16-to-17-year-olds, the VAERS database lists 79 cases of myocarditis or pericarditis. The expected rate in a population that size would be between two and 19 cases.
After Israeli health officials identified a number of myocarditis in its population earlier this year, Pfizer downplayed the potential risk. “Adverse events are regularly and thoroughly reviewed and we have not observed a higher rate of myocarditis than what would be expected in the general population,“ said Pfizer spokesperson Eamonn Nolan in April. “A causal link to the vaccine has not been established. There is no evidence at this time to conclude that myocarditis is a risk associated with the use of Pfizer/BNT COVID-19 vaccine.”
Additionally, not all of the reported cases are accurate, stressed Dr. Tom Shimabukuro, the deputy director of the Immunization Safety Office at CDC. “It’s a bit of an apples-to-oranges comparison because, again, these are preliminary reports,” he said. “Not all these will turn out to be true myocarditis or pericarditis reports.”
The CDC has scheduled an emergency meeting for June 18 to discuss the reports.
CDC has followed 221 discharged patients with the conditions. Some 81% (180) had a full recovery.