Antibody monitoring six months post-COVID-19 vaccination in four healthcare workers: A case series

ABSTRACT

@#This case series described four healthcare workers with exposure to patients and co-workers, who were potential or confirmed cases of COVID-19. They had negative nasopharyngeal swab reverse transcriptase polymerase chain reaction (RT-PCR) tests at different time points and had zero IgG antibodies on VITROS Anti-SARS-CoV-2 IgG Antibody test prior to CoronaVac inoculation on March 1, 2021. The levels of antibody titers, which showed increasing then declining trends of immunoglobulins, were measured at different time points. Although the antibody levels are not proof of immunity against SARS-CoV-2 and the protective quantity is yet to be determined, the titers are evidence that vaccines do elicit an immune response and may have a role in the fight against infection