Modeling the impact of child vaccination (5–11 y) on overall COVID-19 related hospitalizations and mortality in a context of omicron variant predominance and different vaccination coverage paces in Brazil

• Published in: Lancet Regional Health - Americas (Online) 2023-01, Vol.17, p.100396-100396, Article 100396
• Main Authors: Müller, Gabriel Cardozo, Ferreira, Leonardo Souto, Mesias Campos, Felipe Ernesto, Borges, Marcelo Eduardo, Berg de Almeida, Gabriel, Poloni, Silas, Simon, Lorena Mendes, Bagattini, Ângela Maria, Quarti, Michelle, Felizola Diniz Filho, José Alexandre, Kraenkel, Roberto André, Coutinho, Renato Mendes, Camey, Suzi Alves, Kuchenbecker, Ricardo de Souza, Toscano, Cristiana Maria
• Format: Article
• Language: English
• Subjects: Children; COVID-19 vaccines; Infectious disease modeling; SARS-CoV-2 variants; Vaccination
• ISSN: 2667-193X; 2667-193X
• DOI: 10.1016/j.lana.2022.100396

Developing countries have experienced significant COVID-19 disease burden. With the emergence of new variants, particularly omicron, the disease burden in children has increased. When the first COVID-19 vaccine was approved for use in children aged 5–11 years of age, very few countries recommended vaccination due to limited risk-benefit evidence for vaccination of this population. In Brazil, ranking second in the global COVID-19 death toll, the childhood COVID-19 disease burden increased significantly in early 2022. This prompted a risk-benefit assessment of the introduction and scaling-up of COVID-19 vaccination of children. To estimate the potential impact of vaccinating children aged 5–11 years with mRNA-based COVID-19 vaccine in the context of omicron dominance, we developed a discrete-time SEIR-like model stratified in age groups, considering a three-month time horizon. We considered three scenarios: No vaccination, slow, and maximum vaccination paces. In each scenario, we estimated the potential reduction in total COVID-19 cases, hospitalizations, deaths, hospitalization costs, and potential years of life lost, considering the absence of vaccination as the base-case scenario. We estimated that vaccinating at a maximum pace could prevent, between mid-January and April 2022, about 26,000 COVID-19 hospitalizations, and 4200 deaths in all age groups; of which 5400 hospitalizations and 410 deaths in children aged 5–11 years. Continuing vaccination at a slow/current pace would prevent 1450 deaths and 9700 COVID-19 hospitalizations in all age groups in this same time period; of which 180 deaths and 2390 hospitalizations in children only. Maximum vaccination of children results in a significant reduction of COVID-19 hospitalizations and deaths and should be enforced in developing countries with significant disease incidence in children. This manuscript was funded by the Brazilian Council for Scientific and Technology Development (CNPq – Process # 402834/2020-8).