Alam U, Biomndo K, Davis J, Odonde W, Shanks GD, Elbeik T, Bell C, Wasunna KM, Rothel J, Mason C; International Conference on AIDS.
Int Conf AIDS. 2000 Jul 9-14; 13: abstract no. WePeC4441.
U. Alam, American Embassy - Medical Research Unit, American Embassy-MRU, PO Box 30137, Nairobi, Kenya, Tel.: +254-2-729303, Fax: +254-2-714592, E-mail: uzma17@hotmail.com
Background: The extent of tuberculosis infection among the tea plantation workers in Kericho, Kenya is unknown. Over the past 5 years, there has been a four-fold increase in hospitalized admissions for tuberculosis despite directly observed therapy. A pilot tuberculosis study was therefore conducted. Methods: The study was a voluntary cross-sectional survey of adult workers and dependents working on three selected tea estates in Kericho, Kenya. After obtaining informed consent, a tuberculin skin test was placed, presence or absence of bacillus-Calmette-Guerin (BCG) vaccination scar was recorded, and blood drawn for the Quantiferon-TB assay and HIV testing. Results: Of the 938 enrollees, 909 had a tuberculin skin test reading, a valid HIV test result, and Quantiferon-TB assay results and were included in further analysis. Overall, 553 (61%) had a positive tuberculin skin test (TST) defined as transverse induration greater than or equal to 10mm and 512 (56%) had a positive Quantiferon-TB assay for exposure to Mycobacterium tuberculosis or Mycobacterium avium complex. There was substantial agreement between TST and Quantiferon-TB assay with a kappa of 0.77 (p > 0.001). A BCG scar was visible on 537 (59%) of the 909. In these 537 individuals, 387 (72%) had a positive TST and 339 (63%) a positive Quantiferon-TB assay again with a kappa of 0.77 (p > 0.001). Utilizing two different rapid tests, 125 (14%) of the 909 were HIV-seropositive. In these 125 individuals, only 45 (36%) had a positive TST and 34 (27%) had a positive Quantiferon-TB assay with a kappa of 0.84 (p > 0.001). Conclusions: The level of tuberculosis exposure in tea plantation workers as measured by either traditional tuberculin skin testing or Quantiferon-TB assay is consistent with recent World Health Organization estimates. In this setting, both methods were more reactive in BCG vaccinated individuals and substantially less reactive in HIV-seropositive individuals.
Publication Types:
Keywords:
- AIDS Vaccines
- Acquired Immunodeficiency Syndrome
- Adult
- BCG Vaccine
- Biological Assay
- Cross-Sectional Studies
- HIV
- HIV Infections
- HIV Seropositivity
- Humans
- Immunologic Tests
- Kenya
- Mycobacterium bovis
- Mycobacterium tuberculosis
- Population
- Population Groups
- Tuberculin
- Tuberculin Test
- Tuberculosis
- Vaccination
- immunology
Other ID:
UI: 102240707
From Meeting Abstracts