Immunogenicity of the BBIBP-CorV Vaccine; An Observational Study from Pakistan

Objective: To determine the levels of anti-spike protein (S) antibody against SARS-CoV-2 among Vaccinated Healthcare workers of Islamabad.Methodology: Cross-sectional Observational study carried out at HBS General Hospital from March 2021 till May 2021 involving healthcare workers from HBS General Hospital, Rawal General Hospital, Polyclinic Hospital and PIMS. The non-probability sampling technique was used. The study included male and female healthcare workers over the age of 18 who had received their second dose of vaccine at least 2 weeks before sample collection and no more than 8 weeks before sample collection.Results: The study included 123 participants, of whom 6.5% did not have a detectable level of the antibody. The Male to Female ratio was 1.277:1 while mean age was 42.93±13.234 years. Side-effects were experienced by 42.3% (n=52) participants. Significantly higher levels of the antibody were observed in participants who had previous SARS-CoV2 infection and those who experienced vaccine side-effects.Conclusion: The BBIBP-CorV vaccine elicited immunogenicity, leading to detectable anti-spike protein S antibody levels in 93.5% of the patients in our study