Efeitos colaterais das vacinas contra Covid-19 e dengue em pacientes pediátricos

Abstract

Introduction: Vaccination represents one of the greatest advances in public health, being a fundamental strategy for the eradication and control of several infectious diseases. However, vaccine safety remains a determining factor for population adherence, especially in the decision of parents and guardians about the vaccination of children and adolescents. The COVID-19 pandemic, in which 10.44% of global cases occurred in pediatric patients, highlighted the importance of immunization on a universal scale. At the same time, dengue continues to be a global challenge, affecting 95% of affected children more severely, especially in endemic regions, reinforcing the need for effective prevention strategies. Objective: To evaluate the adverse events of COVID-19 and dengue vaccines in children and adolescents, correlating the possible relationship between the occurrence of these events and the number of doses received. Methods: Two systematic reviews and meta-analysis were conducted according to the recommendations of the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA). Both articles used a search strategy for randomized or quasi-randomized controlled trials investigating local and systemic adverse events of COVID-19 and dengue vaccines in children and adolescents, in the following databases: PubMed, Clinicstrial.gov, Cochrane Library, Embase, Web of Science, and Scopus. Risk of bias was assessed using the Cochrane Risk of Bias tool (RoB 2.0), and RevMan 5.4 was used for data synthesis (meta-analysis). In both articles, two authors independently selected and extracted data, with assistance from the third reviewer for disagreements, and the Grading of Recommendations Assessment, Development and Evaluation Working Group (GRADE) approach was used to rate the strength of the evidence. Results: Among the 19 studies analyzed in the systematic review of COVID-19 vaccines, vaccinated pediatric patients had a lower risk of axillary tenderness/swelling (RR = 0.83) after the first dose of protein subunit vaccines and swelling after administration of the first dose of mRNA vaccines (RR = 0.68) compared with the second dose. Adenovirus vector vaccines were associated with a significantly increased risk of local pain (RR = 19.33) after the second dose. Systemic effects such as fever (RR = 0.70), myalgia (RR = 0.68), vomiting (RR = 0.59), and chills (RR = 0.56) were at lower risk after the first dose of mRNA, while irritability/crying (RR = 1.77) were more prevalent after the second dose. Febrile events increased with inactivated (RR = 2.22) and adenovirus (RR = 3.07) vaccines. The third dose followed similar patterns of adverse events. In contrast, in the systematic review and meta-analysis of dengue vaccines, we included 57,836 recipients of tetravalent dengue vaccines. Key findings included: Both vaccines caused significant local pain at the injection site, with TAK-003 showing a higher risk after the full vaccination course and CYD-TDV showing higher local adverse events after the second dose. Systemic side effects, such as headache and myalgia, were more common in CYD-TDV recipients, especially after the first dose. Serious adverse events (SAEs) were reported, but no causal relationship with the vaccines was found. The SAE rate was higher in control groups compared with vaccine groups in most studies. Conclusions: COVID-19 and dengue vaccines demonstrated acceptable safety profiles, with mostly mild and transient adverse events, regardless of dose. Although reactogenicity was observed, adaptive immunity was considered a favorable response and therefore the benefits of vaccination outweigh the potential risks, reinforcing the importance of immunization in disease prevention and community protection. In addition, the need for continuous monitoring and analysis of adverse events allows adjustments to immunization recommendations, ensuring greater safety for vulnerable groups, such as children and adolescents.