Related Experiment Videos
Heaf status 12 years after infant BCG immunization
C Teale1, D B Cundall, S B Pearson
1Leeds Chest Clinic, UK.
Tubercle and Lung Disease : the Official Journal of the International Union Against Tuberculosis and Lung Disease
|August 1, 1992
Summary
Infant BCG immunization provides lasting immunity for most children up to age 12. This study found that most Asian children in Leeds retained immunity from their initial BCG vaccine, reducing the need for repeat immunizations.
Area of Science:
- Pediatrics
- Immunology
- Public Health
Background:
- Uncertainty regarding the long-term effectiveness of infant BCG immunization on Heaf status and immunity.
- BCG vaccination is routinely offered to infants in Leeds, with an uptake of approximately 86% among Asian infants.
- The study addresses the impact of this immunization policy on children's health status.
Purpose of the Study:
- To evaluate the long-term influence of infant BCG immunization on Heaf status and immunity in 12- to 13-year-old children.
- To assess the effectiveness of the current BCG immunization policy in Leeds.
- To determine if prior BCG vaccination impacts the need for re-immunization.
Main Methods:
- Cross-sectional study of 12- to 13-year-old children tested in Leeds in 1988.
- Inclusion of 6363 eligible children (431 Asian) for Heaf testing; 5379 (366 Asian) were tested.
- Analysis of Heaf grades to assess BCG status and infer immunity.
Main Results:
- 90% of Asian children and 92% of non-Asian children tested had a Heaf grade of 0-1, indicating no definite previous BCG.
- A significant proportion of Asian children (75%) who did not require re-immunization likely had persistent immunity from their infant BCG.
- The annual incidence of tuberculosis in Asian children in Leeds was low (6 per 100,000).
Conclusions:
- Infant BCG immunization appears effective in providing appropriate immunity in most children by age 12.
- The study suggests that infant BCG vaccination can prevent the need for repeat BCG immunization in later childhood.
- The findings support the continued use of infant BCG immunization policies.