COVID-19 Vaccine Safety First Year Findings in Adolescents.

BACKGROUND AND OBJECTIVES: The Food and Drug Administration expanded Emergency Use Authorization for use of Pfizer-BioNTech (BNT-162b2) coronavirus disease 2019 vaccine to include people ages 12 years and older on May 10, 2021. We describe adverse events observed during the first full year of the US coronavirus disease 2019 vaccination program for adolescents ages 12 to 17 years. METHODS: We conducted descriptive analyses using data from 2 complementary 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. We reviewed reports and calculated adverse event reporting rates using vaccine administration data. RESULTS: Among 172 032 adolescents ages 12 to 17 years enrolled in v-safe, most reported reactions following BNT-162b2 were mild to moderate, most frequently reported on the day after vaccination, and more common after dose 2. VAERS received 20 240 adverse event reports; 91.5% were nonserious. Among adverse events of interest, we verified 40 cases of multisystem inflammation syndrome in children (1.2 cases per million vaccinations), 34 (85%) of which had evidence of prior severe acute respiratory syndrome coronavirus 2 infection; and 570 cases of myocarditis (17.7 cases per million vaccinations), most of whom (77%) reported symptom resolution at the time of report. CONCLUSIONS: During the first year BNT-162b2 was administered to adolescents ages 12 to 17 years, most reported adverse events were mild and appeared self-limited. Rates of myocarditis were lower than earlier reports. No new serious safety concerns were identified.

Ischemic cardiac events during the Department of Health and Human Services Smallpox Vaccination Program, 2003.

Ten ischemic cardiac events (ICEs) were reported among 37,901 initial US Department of Health and Human Services (DHHS) smallpox vaccinees. Symptoms developed a median of 10 days after vaccination (range, 0-28 days). The median age of case patients was 56 years (range, 42-65 years), and 60% were male. Seven (70%) of the case patients had >/=3 cardiac risk factors or probable coronary artery disease before vaccination. Two women, 55 and 57 years of age, experienced acute myocardial infarction and fatal cardiac arrests. Background rates of ICEs during a 3-week period for civilian populations that were age and sex matched to DHHS vaccinees were estimated. The observed number of myocardial infarctions exceeded estimated expectations (5 vs. 2) but remained within the 95% predictive interval (PI) (0.6-5.4). New onset angina was observed significantly less frequently than estimated expectations (1 vs. 10; 95% PI, 3.5-15.7). After persons with >/=3 cardiac risk factors or known heart disease were deferred from vaccination, no ICEs were reported among an additional 6638 vaccinees.