student research day - Case Western Reserve University School of ...

Canaan Baer
Active Tuberculosis and HIV Case Finding
Canaan Baer, Mary I. Huang and Dr. Christopher Whalen
Department of Epidemiology and Biostatistics
Case Western Reserve University School of Medicine, Makerere University School of Public Health
BACKGROUND: Transmission of tuberculosis is diminished within days of initiating appropriate
treatment; most disease spread occurs before treatment is started. The development of a cost-effective
approach to actively identify cases of tuberculosis is necessary to reduce transmission.
OBJECTIVE: To address Uganda’s TB/HIV burden, we are testing the effectiveness of a community-based
chronic cough survey to actively screen for TB/HIV.
DESIGN: In the Rubaga Division of Kampala, Uganda, we are conducting chronic cough surveys among
residents greater than 15 years old who can communicate in Luganda or English and plan to reside in the
household for >1 week. Identified chronic coughers (cough ≥2 weeks) are further evaluated for TB and
HIV with the Tuberculin Skin Test (TST), sputum microscopy, and HIV testing. If indicated, a physical
exam and chest radiography are performed, and referral is given to appropriate care. Effectiveness of the
chronic cough survey is determined by the number of subjects needed to screen to identify a case of
TB/HIV.
RESULTS: 4202 subjects were surveyed from January to October 2008. The prevalence of tuberculosis in
this population was 0.67%. 148 cases (5.4%) experienced chronic cough. Among the chronic coughers,
71 subjects (48%) had latent TB infection, and 64 (43.2%) were HIV seropositive. Of the chronic
coughers, 29 cases (19.6%) had active tuberculosis; 25 of these cases had a positive AFB sputum smear
(n=20) or culture (n=5). HIV infection was present in 8 cases, giving a prevalence of 5.4% among
chronic coughers and a prevalence of 29.6% among those identified with active disease.
CONCLUSION: Our survey, based on self-reported cough of 2 weeks or more, effectively identifies
members of a community with high likelihood of having active tuberculosis; one would need to evaluate
only 5 chronic coughers to find an additional case of TB. HIV rates were also high among cases of TB.
Supported by the National Institute of Health (T32) Training Grant in Pulmonary Host Defense Infectious
Disease Society of America Medical Scholars Program
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