Immunogenicity Characterization of COVID-19 Vaccines: A Systematic Review and Meta-analysis

• Published in: Revista da Sociedade Brasileira de Medicina Tropical
• Main Authors: Zanair Soares Vasconcelos, Hany Abdulateif Salem, Sâmia Pimenta Veiga, Fabiola Estefany Botelho de Lima, César Rogério da Silva Gonçalves, Eliane Carvalho dos Santos, Alba Regina Jorge Brandão, Kátia Nascimento Couceiro, Jorge Augusto de Oliveira Guerra, Maria das Graças Vale Barbosa Guerra
• Format: Article in Journal/Newspaper
• Language: English
• Published: Sociedade Brasileira de Medicina Tropical (SBMT) 2023
• Subjects: COVID-19; SARS-CoV-2; Vaccines; Immunogenicity; Coronavirus vaccine; Arctic medicine. Tropical medicine; RC955-962; Arctic
• Online Access: https://doi.org/10.1590/0037-8682-0661-2022; https://doaj.org/article/40460e2130ee42089f2e20b8ba30bb5d

ABSTRACT Introduction: Immunogenicity has emerged as a challenge in the development of vaccines against coronavirus disease of 2019 (COVID-19). Immunogenicity is a determinant of the efficacy and safety of vaccines. This systematic review and associated meta-analysis summarized and characterized the immunogenicity of COVID-19 vaccines in randomized controlled trials (RCTs). Methods: Relevant RCTs were systematically sourced from different medical databases in August 2021. The risk ratios and mean differences with 95% confidence intervals were calculated. Results: Of 2,310 papers, 16 RCTs were eligible for review. These RCTs involved a total of 26,698 participants (15,292 males and 11,231 females). The pooled results showed a significant difference in the geometric mean titer between the vaccinated and control groups in favor of the vaccine group after 1 and 2 months of follow-up, for the young age group (18 - < 55y), and with different doses (P < 0.001). The difference in the older age group (>55y) was insignificant (P = 0.24). The seroconversion rate of spike neutralizing antibodies favored the vaccine groups 1 or 2 months after vaccination (P < 0.001). The seroconversion rate of the vaccine group was significantly different (P < 0.001) from that of the control group. Conclusions: Vaccination elicits immunogenicity in the follow-up period for all age groups and at low and large doses. Therefore, people should be encouraged to receive vaccines currently being offered. A boost dose has been asserted for the elderly.