Anti-nucleocapsid Antibody Response After Two Doses of CoronaVac® Among Healthcare Workers

Introduction: The Coronavirus disease-2019 (COVID-19) pandemic that started over two years ago has led to high mortality and morbidity. Vaccine studies have been initiated worldwide to end the pandemic, and the CoronaVac® vaccine was first administered to healthcare workers at high risk of COVID-19 in Turkey. In our study, we aimed to investigate serum antibody levels after vaccination. Materials and Methods: Volunteer healthcare workers without COVID-19 disease who received two doses of CoronaVac® vaccine 28 days apart and were at least 14 days after the last dose of vaccine were included in this study. Assessment of antibodies against Severe acute respiratory syndrome-Coronavirus-2 (SARS-CoV-2) in blood samples from participants was performed using the Elecsys® anti-SARS-CoV-2 electrochemiluminescence immunoassay. Samples with a cut-off index (COI) (COI; signal sample/cut-off)