Survey of Immune Response to COVID-19 Vaccination among Pasteur Institute Employees in Ho Chi Minh City during 2021-2023

Abstract

The COVID-19 vaccine plays a crucial role in minimizing the impact of the pandemic. In Vietnam, during the early stages of the outbreak, vaccine shortages and a rapid increase in cases led to the widespread practice of combining different types of vaccines. To gain a deeper understanding of the immune response after mixed COVID-19 vaccinations, this cross-sectional descriptive study measured anti-SARS-CoV-2 antibody levels following AstraZeneca and then Pfizer BioNTech vaccinations in 274 staff members of the Pasteur Institute in Ho Chi Minh City from April 2021 to January 2023. The results showed that anti-SARS-CoV-2 antibodies were detected in serum one month after the first dose (12.87 IU/mL) and increased significantly one month after the second dose (159.61 IU/ mL) and one month after the third dose (674.36 IU/mL). The study indicated that administering two types of COVID-19 vaccines generated an immune response in the study participants.