Center for Infectious Disease Research and Policy.
By Stephanie Soucheray, MA
Today in Pediatrics researchers published the safety data of the Pfizer-BioNTech (BNT-162b2) COVID-19 vaccine in adolescents ages 12 to 17 years. After 1 year, very few serious adverse events were reported, and instances of myocarditis (inflammation of heart muscle) were lower than initially reported.
The study was conducted using data from two US vaccine safety monitoring systems: v-safe, a voluntary smartphone-based system that monitors reactions and health impacts, and the Vaccine Adverse Event Reporting System (VAERS), the national spontaneous reporting system, the authors said.
The Pfizer two-dose regimen was approved for use in teens in May 2021. From May 2021 to May 2022, 15,493,807 adolescents ages 12 to 17 years received at least one primary dose of BNT-162b2, and 172,032 (1.1%) enrolled in v-safe. The median age of participants in v-safe was 16 years, 54.6% were girls, 62.7% were White, and 73.4% were non-Hispanic or non-Latino.
Most adverse events were mild; among events reported to VAERS, 91.5% were nonserious. Among adverse events of interest, the authors verified 40 cases of multisystem inflammation syndrome in children (1.2 cases per million vaccinations), of which 34 (85%) had evidence of prior COVID-19 infection. They also confirmed 570 cases of myocarditis (17.7 cases per million vaccinations), 77% of which involved symptom resolution at the time of report.
The risk of cardiac disease after COVID-19 infection may be two- to sixfold higher than after vaccination.
“The myocarditis reporting rate was lower for boys ages 12 to 15 years (48.3 cases per million second doses administered) than boys ages 16 to 17 years (84.0 cases per million second doses). These observations are consistent with previous findings that the peak risk group is [in] boys ages 16 to 17 years, although our myocarditis reporting rates are lower than those in early reports,” the authors said.
The authors conclude that the vaccine is safe for this age-group, noting that the risk of cardiac disease after COVID-19 infection may be two- to sixfold higher than after vaccination.