CDC Reschedules Meeting on Reports of Myocarditis Following COVID-19 Vaccination

The US Centers for Disease Control and Prevention (CDC) has rescheduled a special meeting to review cases of myocarditis and pericarditis reported in adolescents and young adults after receiving COVID-19 vaccination.

“The June 18, 2021 COVID-19 meeting is being rescheduled due to the observation of the Juneteenth National Independence Day holiday,” stated the CDC in a notice on its website about the online meeting of its Advisory Committee on Immunization Practices (ACIP).

According to the draft agenda released today, June 21, 2021, the discussion will now take place during 2 sessions held on the first day of the ACIP meeting: June 23, 2021 at 11:30 am.

The first session, “Overview of myocarditis and pericarditis,” will be presented by Matthew Oster, MD, MPH, who is a medical officer at the CDC’s National Center on Birth Defects and Developmental Disabilities. Directly following the first session will be “Update on COVID-19 vaccine safety, including myocarditis after mRNA vaccines,” presented by Tom Shimabukuro, MD, MPH, who is the deputy director of the CDC’s Immunization Safety Office.

Since April 2021, increased cases of myocarditis and pericarditis have been reported in US adolescents and young adults after receiving an mRNA COVID-19 vaccine, with attention focused on those manufactured by Pfizer-BioNTech and Moderna primarily.

On June 10, 2021, Dr Shimabukuro led a presentation to the Food and Drug Administration’s vaccine advisory group, where he highlighted over 700 cases of myocarditis/pericarditis that have been reported across all age groups after the Pfizer-BioNTech and Moderna vaccines, most commonly after the second dose. These cases were mostly reported in men, and the median age for a case of myocarditis after a second dose was 24 years.

Dr Shimabukuro also discussed the 475-preliminary myocarditis/pericarditis cases reported to the CDC’s Vaccine Adverse Event Reporting System (VAERS) in persons aged ≤30 years as of May 31, 2021. Among the 475 reported cases, 226 met the CDC’s “working case definition” of myocarditis and pericarditis and 285 had a known outcome.

Among the 285 cases with a known outcome, 270 were discharged (most to their homes), 15 were still hospitalized, and 3 were in the intensive care unit. Approximately 81% had full recovery of symptoms, according to Shimabukuro.

Among patients aged 16-17 years, there were 79 cases of myocarditis/pericarditis reported after a second dose of vaccine, while the expected number was 2-19 cases, according to Shimabukuro. There were 196 cases in young adults aged 18-24 years, while 8-13 were expected. The case rates per million doses for those age groups were 35 and 21, respectively.

Given the greater risk of other serious COVID-19-related complications, the CDC still recommends that all patients aged ≥12 years be vaccinated against COVID-19. Physicians should consider myocarditis and pericarditis in adolescents or young adults with acute chest pain, shortness of breath, or palpitations.