Trend in HIV prevalence among tuberculosis patients in Tanzania, 1991-1998

OBJECTIVE: To determine the trend in human immunodeficiency virus (HIV) pre valence among tuberculosis patients in Tanzania and estimate what proportio n of the increase in notification rates between the surveys was directly at tributable to HIV infection. METHODS: Consecutive tuberculosis patients were enrolled over 6-month perio ds in most regions. Demographic and clinical data were collected on standar d forms and a single HIV ELISA test performed. Trends in tuberculosis incid ence were estimated from regional notification data. RESULTS: Of 10 612 eligible tuberculosis patients, 44% had HIV infection, c ompared with 32% in the previous survey. The largest increase was observed in the youngest birth cohorts, suggesting active HIV transmission. Approxim ately 60% of the increase in notification rates of smear-positive tuberculo sis between surveys was directly attributable to HIV infection. CONCLUSION: The HIV epidemic has had a strong influence on tuberculosis inc idence. However, since 1995, tuberculosis notification data have increased less steeply, AIDS notifications have gone down, and HIV prevalence in bloo d donors has not increased a great deal. Another survey among tuberculosis patients in 5 years' time may show whether the HN epidemic in Tanzania has reached a maximum or steady state.