Discussion
This article is a comprehensive review of up-to-date clinical findings of the BioNTech-Pfizer vaccine on children and adolescents. We aimed to provide knowledge through the evaluation of existing evidence regarding the BioNTech-Pfizer vaccine on children and adolescents. All published articles were found using a thorough search strategy on three databases (PubMed, Scopus, MEDLINE, and EMBASE Databases) on October 17, 2021, and without restrictions to language or regional. Although children and adolescents have higher levels of antibodies and their immune system response to pathogens is different than adults and most of them have less severe or asymptomatic COVID-19 cases (13), some symptoms were reported for this group after vaccination. The preliminary clinical outcomes of vaccinated children and adolescents suggest common mild symptoms such as fever and headache but also worth noting that some other symptoms such as chest pain is reported, which require further studies and health concerns. The final results of signs and symptoms included 78 vaccinated children and adolescents from 6 studies.
A recent report from Morbidity and Mortality Weekly Report (MMWR) revealed that the hospitalization of COVID-19 related pediatrics during the week ending of August 14th, 2021 was approximately 5 times the rate of the week ending of June 26th, 2021 (29). Moreover, the authors showed that among the children of age 0-4 years during the week ending of August 14th, 2021 was approximately 10 times higher than of the same age by the week ending of June 26th, 2021. In addition, the hospitalization of unvaccinated adolescents of age 12-17 years during the period from June 20-July 31, 2021 was 10.1 times higher than the vaccinated adolescents. The rate of hospitalization for COVID-19–associated pediatrics increased rapidly with the predominance of the Delta variant from June 26 – August 14, 2021. In this study, we found that the hospitalization of vaccinated pediatrics (78 patients) in 6 studies and from April to July, 2021 were less compared to the unvaccinated group. A total of 37 (47%) were hospitalized with a mean range of hospital stay between 1-6 days for the vaccinated pediatrics. ICU admission was reported only for 5 (6.4%) and in only one article with ICU stay for 2-5 days.
Pfizer performed a phase III clinical trial to study the effectiveness of their vaccine. In this study, 2260 children aged from 12 to 15 years were enrolled, only 18 cases of COVID-19 were recorded for the placebo group (n=1129) and none were reported for the vaccinated group (n=1131). Accordingly, the study led to FDA approval of expanding the use to children aged 12 to 15 years (21). Pfizer announced that their COVID-19 vaccine will be 100% efficient in children aged 12 to 15 (30). This emergency use authorization by FDA to include children of 12 to 15 years of age was a significant step in our fight against this virus. Currently, trial studies are still ongoing to further test the vaccine’s efficacy on younger children aged 6 months to 11 years (30).