SEROLOGICAL RESPONSE TO INACTIVATED SARS-COV-2 VACCINE (SINOVAC-CORONAVAC) AMONG HEALTHCARE PROFESSIONALS

• Dr. Ibrahim A. Idris

  Department of Medical Microbiology, University of Khartoum, Sudan

  Author

• Dr. Katarina J. Novak

  Department of Clinical Microbiology, University of Zagreb, Croatia

  Author

This study set out to understand how healthcare workers (HCWs) responded immunologically to two doses of the Sinovac-CoronaVac inactivated SARS-CoV-2 vaccine. We enrolled [Number] HCWs and measured their anti-SARS-CoV-2 spike protein (anti-S) antibody levels. We found high rates of seroconversion ([Percentage]%), meaning most participants developed antibodies. Interestingly, those who had previously been infected with SARS-CoV-2 showed significantly higher anti-S antibody levels (p < 0.001) after vaccination, suggesting a powerful "hybrid immunity." We also observed that older individuals tended to have a weaker antibody response, with age being inversely correlated with antibody levels. Importantly, no severe side effects were reported. These findings confirm that Sinovac-CoronaVac effectively triggers an immune response in this high-risk group and highlight how a previous infection and age can influence how well someone responds to the vaccine. This information is crucial for guiding ongoing monitoring and shaping future vaccination strategies.

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