Abstract
Introduction: Bacillus Calmette-Guérin (BCG) vaccination is routinely administered at birth to prevent severe tuberculosis. Although BCG is generally safe, adverse events may occur. Therefore, this study aimed to describe reported adverse events following BCG vaccination among children referred to healthcare centers in Tehran and Alborz Provinces during one year of follow-up.
Methods: This registry-based prospective descriptive cohort study included 976 children enrolled between September 2022 and February 2024. Participants attending healthcare centers in Tehran and Alborz were followed for one year, with assessments every four months. To this end, parent-reported and clinically documented adverse events were recorded using Rabbit. Finally, SPSS 23 was used for data analysis.
Results: Among 976 participants, 492 (50.4%) were boys and 484 (49.6%) were girls. Diarrhea (4.20%, n = 41), skin rash (2.15%, n = 21), and fever (1.74%, n = 17) were the most frequently reported adverse events. However, decreased milk intake (1.02%, n = 10) and lymphadenopathy (0.61%, n = 6) were less common. All reported events were transient and resolved without hospitalization. Ultimately, no cases of disseminated BCG infection, osteitis, or vaccine-related mortality were observed during the follow-up.
Conclusion: Reported adverse events during the follow-up were uncommon, mild, and self-limited. Given that this descriptive study lacked diagnostic confirmation and a comparison group, no causal relationship could be established between the reported events and BCG vaccination, requiring larger studies to evaluate rare BCG-related complications.