36 | BMC J Med Sci 2023 Comparison of Pre and Post Vaccinated Covid-19 Antibody Titers in General Population Ali Haider 1 , Juwayria Omar 2 , Hameed Mumtaz Durrani 3 , Muhammad Afzal 4 , Abid Ali 5 , Akash John 6 1 BMLS Scholar, Department of Allied Health Sciences, The University of Lahore, Gujrat Campus, 2 Associate professor community medicine, Fazaia Medical College Islamabad, 3 Assistant Professor, Shifa College of Medicine, Islamabad, 4 Biostatistician, Shaheed Zulfiqar Ali Bhutto Medical University, G-8/3, Islamabad, 5 Associate Professor, Department of Allied Health Sciences, The University of Chenab, Gujrat, 6 Lecturer, Department of Allied Health Sciences, The University of Chenab, Gujrat, Correspondence: Ali Haider alihaider535@gmail.com Abstract Objective: The aims and objectives of this study to examine the general population one year later following immunization for changes in anti-SARS-CoV-2 IgG levels. Methodology: The study enrolled 18,610 individuals, including rural and urban areas. The quantities of IgG antibodies were determined using an ELISA. Results: At 5–8 months following complete immunization, both vaccines produced comparable amounts of anti-SARS-CoV-2 IgG. On the other hand, BBIBP-CorV had a much lower IgG concentration. Anti-SARS-CoV-2 IgG levels in a large cohort of volunteers increased nine months after vaccination, indicating asymptomatic infection. Anti-SARS-CoV-2 IgG antibody levels were significantly higher following the booster dose than following the second dose. Antibodies began to build approximately five days after the booster dosage injection and peaked around the fourteenth day. Conclusion: Cut-off dates for the effectiveness of mRNA and vector vaccines appear to be 8–9 months and 5–6 months following vaccination, respectively. With the potential to have a significant impact on the virus's ongoing transmission, providing a booster dose was a brilliant idea. Key words: SARS-CoV-2, IgG antibody, mRNA. Cite this article: Haider A., Omar J, Durrani M, Afzal M, Ali A, John A Comparison of Pre and Post Vaccinated Covid-19 Antibody titers in General Population. BMC J Med Sci. 2023. 4(1): 36-42. Introduction Coronavirus disease 2019 (COVID-19) is caused by the SARS- CoV-2 virus, which has been responsible for the infection of about 440 million people worldwide. COVID-19 was first detected in Pakistan on March 4, 2020. Over 5.69 million cases have been reported since then, resulting in approximately 112,000 deaths. 1 On December 27, 2020, the so-called National Vaccination Program began immunizing healthcare staff in Pakistan against COVID-19, and the program was gradually expanded to include the general population as the population grew older. Vaccinations began in June 2021 for children aged 12-17 years, and in December 2021 for children aged 5-11 years. After nearly a year, more than 53 million people have received anti-COVID-19 immunization. Pakistan's population is predicted to get vaccinated at a rate of 58.5 percent. Almost 30% of those vaccinated had a booster dosage, which is the third and final injection. Prophylactic immunization appears to be the most effective strategy for combating the SARS-CoV-2 pandemic, as it reduces the risk of severe COVID-19, the number of hospitalizations and fatalities from the disease, and brings the pandemic closer to an end. 2,3 In Pakistan, four types of anti- SARS-CoV-2 vaccinations have been delivered. For instance, both the Pfizer/BioNTech, Moderna, AstraZeneca and Sinopharm vaccine employ mRNA technology. The vaccine's nucleoside-modified messenger RNA is encased in lipid nanoparticles to allow non-replicating RNA to enter host cells and transiently express the SARS-CoV-2 virus S antigen. For individuals above the age of 12, Pfizer medication is safe to ingest with a 21-day interval between dosages. It was approved in mid-September 2021 for adults over the age of 50 and healthcare providers to receive the third dosage of the immunization. For seven days to six months following the Authorship Contribution: 1-3 Substantial contributions to the conception or design of the work; or the acquisition, Final approval of the version to be published 4-6 Active participation in active methodology Funding Source: none Conflict of Interest: none Received: Nov 23, 2022 Accepted: Feb 18, 2023 ORIGINAL ARTICLE