Comparison of Antibody Titers From COVID-19 Survivors and Health Workers Getting Two Doses of the Sinovac® Vaccine


Almost two years since becoming a global threat, the whole world is still looking for the best way to reduce the rate of transmission of COVID-19. One of the ways to deal with COVID-19 is to increase immunity by stimulating antibodies in the community. Antibody-mediated humoral responses are critical to prevent viral infections. Antibodies can also be formed through natural processes when someone is infected by SARS-Cov2 or through vaccination programs. In this study, collective blood samples were taken to examine IgG spike receptor binding domains (IgG S-RBD) between two groups: COVID-19 survivors (n = 50) and health workers who were vaccinated twice with the Sinovac vaccine (n = 50). There were no significant differences in antibody levels between the previous COVID-19 infection group and the health workers groups (p = 0.8). 50% (n = 6) of the health workers who were aged 30-39 had excellent titer antibody levels, as did 50% (n=7) of the COVID-19 survivors group who were in their 30s. Further research is needed to decide the perfect time for booster shots.

Keywords: COVID-19, titer antibody, IgG S-RBD, Sinovac

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