COVID-19 Immunization for Adolescents: What does the Scientific Evidence Tell us?

Le résumé fourni par la source

On January 30, 2020, the WHO Director-General declared the COVID-19 outbreak a Public Health Emergency of International Concern (PHEIC).[1] It was an unprecedented experience in the history of humankind, and there was fear, confusion, and sorrow due to the deaths of near and dear ones, besides huge economic losses. The priority for COVID-19 in terms of funding, human resources, and infrastructure resulted in negligence toward other public health programs. Following the vaccination of adults (susceptible to disease and death from COVID-19), the momentum for immunization of adolescents aged 12–17 years was started in the West, although they rarely suffered serious disease. It is based on the presumption that adolescents may serve as the source of transmission in the community due to their social mixing patterns, which trigger community outbreaks.[2] The data on such transmission were not available. In this editorial, we provide an overview of studies on COVID-19 immunization among adolescents, which will provide insights that may help in rational decision-making in the future. On May 10, 2021, the Food and Drug Administration (FDA) expanded Emergency Use Authorization (EUA) for the use of the Pfizer-BioNTech (BNT-162b2) COVID-19 vaccine for people aged 12 years and above. Subsequently, Hesse et al.[3] (2023) reported that 172,032 adolescents aged 12–17 were enrolled in v-safe. Many reported mild to moderate reactions following BNT-162b2, most frequently on the day after vaccination – and more common after the second dose. Vaccine Adverse Event Reporting System (VAERS) received 20,240 adverse event reports, of which 91.5% were not serious. However, 9.5% had more serious adverse reactions (i.e.,1922 events). This included 39 cases of multisystem inflammatory syndrome in children (MIS-C) (1.2 cases per million vaccinations), and 33 of these had evidence of prior SARS-CoV-2 infection. There were 570 cases of myocarditis (17.7 cases per million vaccinations), of whom 23% had long-term residual effects. The data from postauthorization safety monitoring of BNT-162b2 primary series vaccination during the first 3 months reported 61–122 cases of myocarditis per million adolescent boys vaccinated.[4-6] Wang and Zhu stated that the omicron and delta variants have led to a significant increase in adolescent hospitalization rates,[2] but the reference they cited describes only the high prevalence of antibodies among adolescents without any mention of hospitalization.[7] Even at the peak of the pandemic, there were hardly any hospital admissions of children due to COVID-19.[8] In Sweden, which kept its schools open, there were very few instances of admissions for COVID-19.A study of severe COVID-19 among Swedish schoolchildren found that only one child out of 130,000 children required admission to an intensive care unit during 4 months of data collection, and there were no reports of deaths.[9] Figueroa et al.[10] reported that the omicron-containing mRNA-1273.222 vaccine had favorable safety and immunogenicity in adolescents. However, a careful assessment of this study is needed. Of 379 study participants, 229 (61%) reported at least one solicited adverse reaction within 7 days of vaccination and systemic adverse reactions were reported by 150 (40%) participants. In this study, all 379 participants were SARS-CoV-2-positive at baseline, which vitiated efforts to determine the immunogenicity of the novel vaccine. A detailed narrative review by Diani et al.[11] highlights that individuals exposed to COVID-19 develop natural immunity (both cell-mediated and humoral), which is effective in the long run and protects against serious illness and reinfection compared to vaccine-induced immunity, which decays faster than natural immunity. Concerns have also been raised about a higher risk of adverse effects on the heart (possibly from the increased serological response) among those with “hybrid immunity”, that is, from the natural infection and the vaccine.[12] According to the Centres for Disease Control and Prevention (CDC), while cases of myocarditis and pericarditis are rare, they are mostly seen in adolescent and young adult males within 7 days after receiving the second dose of the vaccine.[13] Similarly, the data from clinical trials of the Novavax COVID-19 vaccine and postauthorization vaccine safety monitoring outside the United States suggest an increased risk of myocarditis and pericarditis following Novavax vaccination.[13] Whatever little data are available do not support the spread of infection from young people to adults. Also, given the low risk of severe disease and significant adverse events in this age group, the precautionary principle demands pausing the COVID-19 vaccination among adolescents till these thorny issues are resolved. As far as India is concerned, the fourth nationwide serosurvey showed that the prevalence of SARS-CoV-2 antibodies (IgG) in the general population aged ≥6 years was 81% (95% CI 79.6% to 82.3%) among those who had received one vaccine dose and 89.8% (95% CI 88.4% to 91.1%) among those who received both doses of vaccine.[14] Given such high seropositivity, proposing an additional vaccination for adolescents (which involves significant side effects), as reported in the above studies, appears unjustified. Data availability statement NA. Author contribution NA.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.