Related Experiment Videos
Active case finding: understanding the burden of tuberculosis in rural South Africa
P M Pronyk1, B Joshi, J R Hargreaves
1Department of Community Health, University of the Witwatersrand, Johannesburg, South Africa. pronyk@soft.co.za
Setting:
The Agincourt demographic and health surveillance site in South Africa's rural Northern Province.
Objectives:
To accurately assess the true burden of tuberculosis in a rural sub-district with a known high prevalence of human immunodeficiency virus.
Design:
Data on hospital registrations of tuberculosis were combined with data from an ongoing demographic health and surveillance system to accurately describe the burden of tuberculosis in a well-defined community. Undiagnosed active cases of sputum-positive disease in the community were detected among chronic coughers identified by heads of household during a single-pass census interview.
Results:
The incidence of hospitalised tuberculosis among the permanently resident population (n = 56 566) was 212/100,000 person-years during 1999. The average point prevalence of detected tuberculosis (all forms) among patients aged over 10 years was 133/100,000, and 81/100,000 for sputum-positive pulmonary disease. This compares with a point prevalence of 16/100,000 cases of sputum-positive disease detected through active case finding.
Conclusion:
For every nine cases of sputum positive pulmonary tuberculosis being treated at any one time, there are two cases of undiagnosed disease in the community. This study demonstrates a modest burden of undiagnosed tuberculosis among residents in a rural sub-district in South Africa.