Antigenic drift in SARS-CoV-2: diminished vaccine protection in pediatric populations against Omicron and its JN.1 subvariant
Year: 2025
Type: article
Study design: Observational Study
Abstract: Background The COVID-19 vaccination campaign for children in Brazil evolved gradually from 2021 to the present, adapting to regulatory framework from the Brazilian Health Regulatory Agency (ANVISA). However, while adults received updated vaccines targeting newer variants, children and adolescents continued to receive vaccines based on the original wild-type strain.Research design and methods This study evaluates the vaccine-induced protective immunity, measured by serum antibody and neutralization responses, in vaccinated (n = 61) and unvaccinated (n = 13) pediatric populations against the wild-type (WT), Omicron BA.1, and JN.1 SARS-CoV-2 variants.Results Vaccinated children exhibited significantly higher antibody levels and neutralization titers against WT compared to unvaccinated peers (p ≤ 0.0001). However, responses to BA.1 were drastically reduced, and JN.1 subvariant neutralization was limited in both groups. Immunoinformatic analysis revealed a marked decline in conserved neutralizing antibody-targeting epitopes within the Spike protein: from 465 in WT to 49 in BA.1 and 41 in JN.1. This substantial antigenic drift underscores the immunological gap created by vaccinating children with outdated formulations.Conclusions Our findings highlight the urgent need for updating pediatric vaccines to include antigens from circulating virus variants in order to increase immune protection and reduce susceptibility to infection and controlling community transmission.
Source: Expert Review of Vaccines
Authors: Jéssica Pires Farias, Milena Silva Souza, Mayanna Moreira Costa Fogaça, Ruth Dálety da Silva Brito, Amanda da Rocha Santos, Cristiane Moutinho Lagos de Melo, Georon Ferreira de Sousa, Carla Torres Braconi, Mario Gabriel Lopes Barboza, Vanesca de Souza Lino, Érika Donizetti Candido, Paloma Oliveira Vidal, João Renato Rebello Pinho, Danielle Bruna Leal Oliveira, Edison Luiz Durigon, Luís Carlos de Souza Ferreira, Jaime Henrique Amorim
Language: English
Subfield: Infectious Diseases
Field: Medicine
Domain: Health Sciences
Open Access status: diamond
Funders: Fundação de Amparo à Pesquisa do Estado de São Paulo, Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, Ministério da Ciência, Tecnologia e Inovação, Conselho Nacional de Desenvolvimento Científico e Tecnológico, Financiadora de Estudos e Projetos, Fundação de Amparo à Pesquisa do Estado da Bahia, Universidade Estadual de Campinas, Universidade Federal de Minas Gerais
Awards: G1510646110, G1857755600, G1928200323, G2031750972, G2070215119, G2823776494, G286797336, G3024807003, G3461889728, G3697280865, G4374289430, G4860148628, G4914476353, G5429399760, G5580252856, G5850506195, G5851865575, G6191138830, G6244628984, Drug discovery against human viral infectious diseases, G6315019847, G6480762056, G654803073, G6710322829, G674028141, G7053055693, G7318746289, G7513797925, G7649111399, G803616303, Vaccination against COVID-19: understanding the past and present and designing the future, Development of SARS-CoV-2 auto-assembly protein-based nanovaccines, Evaluation of humoral immune response and inflammatory response in patients with confirmed diagnosis of COVID-19 at Hospital Sírio Libanês and correlation with disease severity, G8826289832, G8886823181
OpenAlex ID: W4416815731