Related Experiment Videos
Evaluation of the efficacy of routine BCG vaccination: a case-control study
1Community Medicine Department, Faculty of Medicine Ain, Shams University, Cairo, Egypt.
Insights
Routine BCG vaccination offers moderate protection against childhood pulmonary tuberculosis in Cairo, Egypt. The study found 53% efficacy, slightly reduced to 49% after accounting for crowding.
Area of Science:
- Public Health
- Pediatrics
- Infectious Diseases
Background:
- Childhood pulmonary tuberculosis remains a significant health concern globally.
- Bacille Calmette-Guérin (BCG) vaccination is the primary method for preventing severe forms of tuberculosis in children.
- Understanding BCG efficacy in diverse populations is crucial for public health strategies.
Purpose of the Study:
- To evaluate the protective efficacy of routine BCG vaccination against childhood pulmonary tuberculosis in Cairo, Egypt.
- To assess the impact of confounding factors, such as crowding, on BCG vaccine effectiveness.
Main Methods:
- A case-control study design was employed in metropolitan Cairo.
- 175 children with pulmonary tuberculosis (cases) were matched with two controls each, based on residence.
- Vaccination status was determined through maternal recall and physical examination for BCG scar.
Main Results:
- The overall crude efficacy of BCG vaccination against childhood pulmonary tuberculosis was 53% (95% Confidence Interval: 31%-68%).
- After adjusting for the crowding index, the estimated vaccine efficacy decreased to 49% (95% Confidence Interval: 25%-57%).
Conclusions:
- Routine BCG vaccination demonstrates a notable protective effect against childhood pulmonary tuberculosis in the studied Cairo population.
- Factors like household crowding may influence the real-world effectiveness of the BCG vaccine.
- Further research is warranted to explore potential biases and optimize BCG vaccination strategies.
Abstract:
A case-control study was conducted in a metropolitan region of Cairo, Egypt to determine the protective efficacy of routine BCG Vaccination of infants against childhood pulmonary tuberculosis. A total of 175 cases of children suffering from pulmonary tuberculosis were obtained over 8 months period from hospitals likely to admit such cases in Cairo. Each case was matched to two controls for the district of residence. Vaccination status of cases and controls was ascertained by asking the mothers and confirmed by examination of the left arm of the study children for the scar of BCG vaccination. The overall crude efficacy of BCG vaccination was found to be 53% (CL: 68%, 31%), dropping to 49% (CL: 57%, 25%) after controlling for the confounding effect of crowding index. Potential biases in the study design and their role in over or underestimation of the vaccine efficacy were discussed.