Comparison of Antibody Responses After CoronaVac and BNT162b2 Vaccines in Healthcare Workers

Abstract

Since the initial outbreak in late December 2019, the coronavirus disease 2019 (COVID-19) pandemic has become a significant healthcare issue worldwide. Despite patients getting the total recommended doses of the COVID-19 vaccine, it is still unable to stop the spread of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Our study aimed to evaluate the antibody response in the 3rd month after two doses of the CoronaVac vaccine and after a single dose of the BNT162b2 vaccine. One hundred thirty-five people from Tarsus State Hospital health workers were included in the study. We collected serum samples from healthcare workers 3 months post-vaccination, and the Anti-SARS-CoV-2 Quanti-Vac ELISA IgG kit coated with recombinant S1 antigen was used to test for SARS-CoV-2 antibodies. Antibody levels of BNT162b2 (last vaccine) patients are significantly higher than CoronaVac ones (p < 0.05). It was determined that those who do not have a concomitant disease and those who do not smoke have higher antibody levels after CoronaVac than the others (p < 0.05). It was determined that 53.1% of 32 patients with pain, swelling, redness at the vaccination site after CoronaVac did not have pain/swelling/redness at the vaccination site after BNT162b2 (p < 0.05). Headache was also more common after CoronaVac compared to the BNT162b2 vaccine (p < 0.05). In conclusion, IgG seropositivity was lower after CoronaVac than BNT162b2, and the antibody level for CoronaVac recipients has decreased over time since vaccination, but not for BNT162b2 recipients.

Keywords: Anti-SARS-CoV-2 IgG; COVID-19; Healthcare workers; SARS-CoV-2.