COVID-19 immunity after vaccination in the population of the Portuguese province Beira Baixa

Abstract

Introduction The high emergency in the control of the pandemic has determined that the scientific community is dedicated to the production of effective vaccines for immunization against SARS-CoV-2. With the emergence of new variants of SARS-CoV-2, there was a need to increase immunity in the vaccinated population through a booster dose. The booster dose is allowed to increase the immunity of individuals and, consequently, reduce the probability of reinfection, as well as severe symptoms associated with COVID-19. Objective To evaluate the acquired immunity to COVID-19 through vaccination, and to verify the influence of the booster dose on the antibody’s concentration. Materials and Methods Data were collected from 965 individuals of both genders and vaccinated for COVID-19. Results 91.8% of the sample had neutralizing antibodies against SARS-CoV-2, and the group of fully vaccinated individuals had a higher percentage of neutralized antibodies compared to individuals who did not have a booster dose (53.2% vs. 38 .7%). Discussion Neutralizing antibodies were found in 91.8% of the sample, which demonstrates the effectiveness of vaccination in the production of antibodies. The results demonstrated the effectiveness of the booster dose in the production of neutralizing antibodies against SARS-CoV-2. Conclusion Vaccination was quite effective in producing neutralizing antibodies. In addition, booster vaccination increased humoral immunity.