CoronaVac is one of the most widely administered COVID-19 vaccines in Indonesia. Previous studies have documented its effectiveness in protecting against COVID-19 in several countries. This study aimed to assess the long-term immunogenicity of CoronaVac in individuals with comorbidities or a history of SARS-CoV-2 infection. The total anti-N Ig and anti-S-RBD Ig levels at 7 and 26 weeks after the second dose of vaccine were documented in 194 health workers. The participants were divided into groups based on their comorbidities and history of SARS-CoV-2 infection. The antibody titers did not differ according to comorbidity status or history of SARS-CoV-2 infection. The total anti-nucleocapsid Ig and total anti-S-RBD Ig levels were significantly lower in individuals without a history of SARS-CoV-2 infection. These results indicate that CoronaVac induces a lower specific antibody response than natural infection and less long-term immunogenicity.
Keywords: COVID-19; CoronaVac; anti-S-RBD Ig; anti-nucleocapsid Ig; comorbidities.