ABSTRACT
The rapid emergence of COVID-19 variants of concern (VOCs) has hindered vaccine uptake. To inform policy, we investigated the effectiveness of the BNT162b2 vaccination among adolescents against symptomatic and severe COVID-19 diseases using mostly real-world data (15 studies). We searched international databases until May 2022 and used Cochrane's risk of bias tools for critical appraisal. Random effects models were used to examine overall vaccine effectiveness (VE) across studies (general inverse-variance) and the effect of circulating VOCs on VE (log relative ratio and VE). Meta-regression assessed the effect of age and time on VE (restricted-maximum likelihood). BNT162b2 VE against PCR-confirmed SARS-CoV-2 was 82.7% (95%CI: 78.37-87.31%). VE was higher for severe (88%) than non-severe (35%) outcomes and declining over time improved following booster dose in omicron era [73%(95%CI:65-81%)]. Fully vaccinated adolescents are protected from COVID-19 circulating VOCs by BNT162b2 especially for the need of critical care or life support.
Subject(s)
COVID-19 , Adolescent , Humans , COVID-19/prevention & control , SARS-CoV-2 , BNT162 Vaccine , Vaccination , RNA, MessengerABSTRACT
Myocarditis and pericarditis are frequent complications of COVID-19, but have also been reported following vaccination against COVID-19 in adolescents. To build vaccine confidence and inform policy, we characterized the incidence of myocarditis/pericarditis in adolescents following BNT162b2 vaccination and explored the association with dose and sex. We searched national and international databases for studies reporting the incidence of myocarditis/pericarditis following BNT162b2 vaccination as the primary endpoint. The intra-study risk of bias was appraised, and random-effects meta-analyses were performed to estimate the pooled incidence by dose stratified by sex. The pooled incidence of myocarditis/pericarditis was 4.5 (95%CI: 3.14-6.11) per 100,000 vaccinations across all doses. Compared to dose 1, the risk was significantly higher after dose 2 (RR: 8.62, 95%CI: 5.71-13.03). However, adolescents experienced a low risk after a booster dose than after dose 2 (RR: 0.06; 95%CI: 0.04-0.09). Males were approximately seven times (RR: 6.66, 95%CI: 4.77-4.29) more likely than females to present myocarditis/pericarditis. In conclusion, we found a low frequency of myocarditis/pericarditis after BNT162b2, which occurred predominantly after the second dose in male adolescents. The prognosis appears to be favorable, with full recovery in both males and females. National programs are recommended to adopt the causality framework to reduce overreporting, which undercuts the value of the COVID-19 vaccine on adolescent life, as well as to extend the inter-dose interval policy, which has been linked to a lower frequency of myocarditis/pericarditis.
ABSTRACT
BACKGROUND: This study aimed to evaluate the safety and effectiveness of the BNT162b2 vaccine in immunocompromised adolescents and young adults. RESEARCH DESIGN AND METHODS: The study conducted a meta-analysis of post-marketing studies examining BNT162b2 vaccination efficacy and safety among immunocompromised adolescents and young adults worldwide. The review included nine studies and 513 individuals aged between 12 and 24.3 years. The study used a random effect model to estimate pooled proportions, log relative risk, and mean difference, and assessed heterogeneity using the I2 test. The study also examined publication bias using Egger's regression and Begg's rank correlation and assessed bias risk using ROBINS-I. RESULTS: The pooled proportions of combined local and systemic reactions after the first and second doses were 30% and 32%, respectively. Adverse events following immunization (AEFI) were most frequent in rheumatic diseases (40%) and least frequent in cystic fibrosis (27%), although hospitalizations for AEFIs were rare. The pooled estimations did not show a statistically significant difference between immunocompromised individuals and healthy controls for neutralizing antibodies, measured IgG, or vaccine effectiveness after the primary dose. However, the evidence quality is low to moderate due to a high risk of bias, and no study could rule out the risk of selection bias, ascertainment bias, or selective outcome reporting. CONCLUSIONS: This study provides preliminary evidence that the BNT162b2 vaccine is safe and effective in immunocompromised adolescents and young adults, but with low to moderate evidence quality due to bias risk. The study calls for improved methodological quality in studies involving specific populations.
Subject(s)
BNT162 Vaccine , COVID-19 , Immunocompromised Host , Immunogenicity, Vaccine , Adolescent , Adult , Child , Humans , Young Adult , BNT162 Vaccine/immunology , COVID-19/prevention & control , VaccinationABSTRACT
The COVID-19 pandemic has severely affected adolescents. Safe and effective vaccines are pivotal tools in controlling this pandemic. We reviewed the safety profile of the BNT162b2 COVID-19 vaccine in adolescents using mostly real-world data to assist decision-making. We used random-effects model meta-analysis to derive pooled rates of single or grouped adverse events following immunization (AEFI) after each primary and booster dose, as well as after combining all doses. Reporting on over one million participants with safety data were included. The most-reported local and systemic AEFIs were pain/swelling/erythema/redness and fatigue/headache/myalgia, respectively. AESIs were rarely reported but were more frequent after the second dose than they were after the first and the booster doses. Health impact was less common among adolescents after receiving BNT162b2 vaccine. Rare life-threatening AEFIs were reported across all doses in real-world studies. Our findings highlight the significance of enhancing national and regional vaccination programs to ensure public confidence.