Neutralizing antibody titers after COVID-19 vaccination

Background: Monitoring COVID-19 and evaluating the effectiveness of prevention and control strategies are considered critical priorities in public health. As a result, the administration of COVID-19 vaccines has been widely approved around the world. In the current study, we investigated the level of severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) neutralizing antibody (NAb) among individuals who received different COVID-19 vaccines. Methods: This cross-sectional study recorded demographical data and clinical characteristics of 168 individuals who received COVID-19 vaccines from 2021 to 2022. Vaccination data of participants, including type and times of vaccine and any complications and symptoms after vaccination, were also recorded. SARS-CoV-2 NAb level was assessed by performing an ELISA test, and all data was analyzed using SPSS version 21. The significant level was set at 0.05. Results: The mean age of the participants was 40.4 ± 16 years, and 109 were females. About 18.4 % of participants had the underlying diseases, of which thyroid diseases were the most frequent. The mean SARS-CoV-2 NAb level was 31.6 ± 39.78 ng/ml. Sinopharm was the common vaccine in our population, and AstraZeneca represented a high level of Nab 47.18 ng/ml. Among the participants, 96 had mild to severe complications after vaccination, with the most complaining of arm pain. Significant differences of NAb levele were observed only between types of vaccine and gender (P < 0.05). Conclusion: Due to our findings, all employed vaccines demonstrated efficacy in generating NAb. The levels of Nab were different among genders, age groups, and different types of vaccine receivers.