LESSONS LEARNED: AN IN-DEPTH LOOK AT SINO PHARM VACCINE RESEARCH IN KARACHI PAKISTAN OBSERVATIONAL STUDY

Abstract

Background: The global COVID-19 pandemic has led to widespread efforts in developing effective vaccines to control the spread of SARS-CoV-2. The Sinopharm BBIBP-CorV vaccine, an inactivated virus vaccine developed by the Beijing Institute of Biological Products, received emergency use authorization from the World Health Organization (WHO). Despite its global distribution, limited real-world safety data exist for specific populations, particularly in low- and middle-income countries like Pakistan.

Objective: This study aimed to evaluate the safety profile and incidence of adverse events following immunization (AEFI) associated with the Sinopharm vaccine among the population of Karachi, Pakistan.

Methods: A prospective observational study was conducted over 56 days, including 5,420 participants vaccinated with the Sinopharm BBIBP-CorV vaccine. Data were collected using structured questionnaires and follow-up interviews, focusing on demographic information, comorbidities, and post-vaccination adverse effects. Descriptive statistics were applied to assess the frequency and severity of AEFI, while chi-square tests evaluated associations between adverse events and demographic factors.

Results: Out of 5,420 vaccinated individuals, 24 (0.442%) reported adverse effects. Of these, 23 cases (95.8%) occurred after the first dose and 1 case (4.2%) after the second dose. Female participants accounted for 79.2% of AEFI cases, while males represented 20.8%. The most affected age group was 41–50 years, comprising 45.8% of AEFI cases. Common adverse effects included headache (41.7%), vertigo (20.8%), and dizziness (16.7%). Comorbidities such as hypertension and diabetes showed no significant association with AEFI occurrence.

Conclusion: The Sinopharm vaccine demonstrated a strong safety profile, with mild and self-limiting adverse effects observed in a small fraction of participants. These findings support its continued use in mass immunization campaigns, reinforcing its role as a reliable tool against COVID-19.