Evaluation of antibody levels induced by sars-cov-2 infection or covid-19 vaccination

ABSTRACT

BACKGROUND AND AIM: SARS-CoV-2 has caused a pandemic and COVID-19 challenged both human and public health over the world. Different types of COVID-19 vaccines were developed against the disease virus with various techniques. In this research, it was aimed to evaluate the antibody responses induced by mRNA vaccines and inactivated vaccines or SARS-CoV-2 infection. METHODS: Between January and August 2021, 651 patients tested for immunoglobulin G antibody levels against the spike protien of SARS-CoV-2. Antibody levels(AU/mL) were detected by Chemiluminescence-Microparticle-Immunoassay, detection was carried on Abbott-Architect ci8200-Autoanalyzer. RESULTS: Among 651 patients 298 of them were vaccinated without previous COVID-19 history (77 mRNA, 221 inactivated), 123 were infected with SARSCoV-2 and not vaccinated, 58 were vaccinated after the infection (19 mRNA, 39 inactivated) while 172 of all did not have previous infection or vaccination history. of 172 patients 29 of them tested positive for anti-Spike antibody levels with a median value of 223.9. Inactivated vaccine induced antibody responses were significantly lower than mRNA vaccine induced levels (p=0.000, median304.5, 7530.8 respectively). In previously infected population who were not vaccinated;higher antibody levels were observed than inactivated vaccine administred patients (p=0.000, median737.1, 304.5 respectively), when compared to the patients who received mRNA vaccine antibody levels were found to be lower (p=0.000, median737.1, 7530.8). Among the patients who were vaccinated after the infection;latterly mRNA vaccine administred patients were found to have higher antibody levels than patients who received inactivated vaccine after the infection (p=0.000, median12070.4, 1183.9 respectively). CONCLUSIONS: Higher levels of antibody response were observed in patients who received mRNA vaccine when compared to those who received inactived vaccine or were infected with SARS-CoV-2. The highest levels were observed among patients who were infected then also received mRNA vaccine. This study whose preliminary data were examined should be supported by larger sample groups and longer follow-up with further studies.