Evaluation of the effectiveness and adverse effects of COVID-19 vaccines administered at Kashan University of Medical Sciences

Objectives: The development of protective immunity through COVID-19 vaccines is influenced by both host factors and the composition of the vaccine. Therefore, it is essential to assess the efficacy and side effects of different vaccines among individuals with diverse socioeconomic and genetic backgrounds.Methods: In this cross-sectional descriptive study, we examined 192 vaccinated individuals (126 recipients of Sinopharm and 66 recipients of AstraZeneca) for neutralizing antibodies two to four weeks after receiving their second vaccine dose. Additionally, we monitored these individuals for the presence or absence of COVID-19 symptoms and adverse effects over a one-month period following vaccination.Results: There was no significant difference in mean antibody titers between the Sinopharm and AstraZeneca vaccine groups (p=0.452). The percentage of positive antibody results in the Sinopharm and AstraZeneca groups was 69.8% and 84.8%, respectively, with no statistically significant variance (p=0.437). The most common side effect reported in the Sinopharm group was malaise (87.3%), while in the AstraZeneca group, malaise was also prevalent (95.5%). Compared to Sinopharm, the AstraZeneca group experienced a higher incidence of side effects (p<0.05). However, the Sinopharm group had a higher percentage of injection site pain as a complication (p<0.001).Conclusion: Our study revealed that there is no significant difference in efficacy between Sinopharm and AstraZeneca vaccines in individuals without a history of COVID-19. Common side effects following COVID-19 vaccination were observed in both Sinopharm and AstraZeneca recipients, with higher frequencies noted in the AstraZeneca group in most cases. This information may aid individuals who are concerned about potential vaccine side effects in making informed decisions.