Introduction: Vaccines function through a variety of methods to provide disease protection; nevertheless, the process of establishing immunity can create side effects.
Objectives: The purpose of this research was to determine the acute side effects of two COVID–19 immunizations that are commonly used in the Karachi population.
Materials and Methods: Between August and September of 2021, a cross-sectional analytical survey was carried out. The 291 immunization recipients were asked to complete a survey concerning the vaccine's side effects. The Chi-Square test was used to compare the post-vaccination side effects of categorization groups. A p-value of ≤0.05 was statistically significant.
Results: Among post-vaccination side effects, fever was reported by 32.3% of the participants, followed by fatigue, redness at the injection site and gastrointestinal disturbances. The results show association of minor adverse effect with Gender and history of COVID infection.
Conclusion: In conclusion, vaccines are a potent weapon for controlling the COVID-19 pandemic, with high efficacy and low adverse reactions. The most common side effects of the Sinopharm and Sinovac vaccination was found to be fever, and there was a linear association between the presentations of most of the adverse effects and the history of Covid-19 infection.