COVID-19 Vaccination in Pediatrics: Was It Valuable and Successful?

Abstract

Background: The mass vaccination of children against coronavirus 2019 disease (COVID-19) has been frequently debated. The risk-benefit assessment of COVID-19 vaccination versus infection in children has also been debated.

Aim: This systematic review looked for answers to the question "was the vaccination of our children valuable and successful?".

Methods: The search strategy of different articles in the literature was based on medical subject headings. Screening and selection were based on inclusion/exclusion criteria.

Results and discussion: The search results revealed that the majority of the reported adverse events after COVID-19 vaccination in pediatrics were mild to moderate, with few being severe. Injection site discomfort, fever, headache, cough, lethargy, and muscular aches and pains were the most prevalent side effects. Few clinical studies recorded significant side effects, although the majority of these adverse events had nothing to do with vaccination. In terms of efficacy, COVID-19 disease protection was achieved in 90-95% of cases for mRNA vaccines, in 50-80% of cases for inactivated vaccines, and in 58-92% of cases for adenoviral-based vaccines in children and adolescents.

Conclusions: Based on available data, COVID-19 immunizations appear to be safe for children and adolescents. Furthermore, multiple studies have proven that different types of vaccines can provide excellent protection against COVID-19 in pediatric populations. The efficacy of vaccines against new SARS-CoV-2 variants and the reduction in vaccine-related long-term adverse events are crucial for risk-benefit and cost-effectiveness assessments; therefore, additional safety studies are required to confirm the long-term safety and effectiveness of vaccinations in children.

Keywords: COVID-19; adverse events; efficacy; pediatrics; safety; types; vaccination.

Figure 1

Flowchart of the article selection process.

Figure 2

Mechanisms influencing the vulnerability of adults and children to SARS-CoV-2 infection. Increased expression of mediators essential for viral entry into airway epithelial cells (ACE-2 and TMPRSS2) in adults combined with the proinflammatory milieu may predispose the adult lung to serious pulmonary injury and progression to acute respiratory distress syndrome (ARDS). The pediatric lung has greater expression of immunomodulatory cytokines and possibly a decreased expression of viral entry mediators.

Figure 3

A chronology of significant events in the development of COVID-19 vaccines. The Emergency Use Authorization (EUA) of BNT162b2 happened shortly after the appearance of alpha and beta variants in the UK in December 2020. The WHO granted EUA for the adenovirus vector-based vaccine AZD1222, the inactivated vaccines by Sinopharm and Sinovac, and the protein subunit vaccine NVX-Co2373 in 2021. The FDA approved the use of the mRNA-1273 vaccine in children and adolescents from 6 months to 17 years of age in 2022.

Figure 4

Possible COVID-19 vaccine complications. The following complications have been potentially associated with COVID-19 vaccines: (1) coagulation disorders (thrombocytopenia); (2) heart diseases (myocarditis); (3) lymphatic system diseases; (4) immune diseases (allergic reactions, autoimmune hepatitis, and thyroid diseases); (5) nervous system disorders (functional neurological disorders); and (6) other diseases (Rowell’s syndrome, macular rash, and chilblain-like lesions)].