ASSOCIATION BETWEEN LEPROSY AND HIV-INFECTION IN TANZANIA

Setting: An epidemiological study of the interaction of leprosy and HI V infection in Tanzania. Objective: To establish the prevalence of HIV infection among leprosy patients, and to measure the association of H IV and leprosy by comparing the HIV prevalence in leprosy patients and blood donors. Design: Testing for HIV infection in consecutively diag nosed leprosy patients (new and relapsed after MDT) in all regions in Tanzania successively for a period of 3 to 6 months during 1991, 1992 and 1993. Results: Out of the total estimated eligible leprosy patient s, 697 patients (69%) entered the final analysis. The HIV prevalence a mong these leprosy patients was 12% (83/697) as compared to 6% (8960/1 58,971) in blood donors examined in Tanzania during the same period, T here were no significant differences in HIV seroprevalence by age, sex , residence or type of disease. However, the adjusted odds ratio (OR) of the presence of a BCG scar was 1.9 [95% confidence interval (CI) 1. 1-3.3] among HIV-positive leprosy cases compared to HIV-negative lepro sy cases, Comparing leprosy cases with blood donors as controls, the l ogistic regression model, controlling for sex, age group and residence , showed the OR for HIV seropositivity among leprosy patients to be 2. 5 (95% CI 2.0-3.2). This association existed in all strata, but was st rongest in the 15-34-year age group. No difference of HIV status betwe en multibacillary and paucibacillary leprosy could be shown to exist, The point estimate of the population attributable risk of HIV infectio n for leprosy was 7%. Conclusion: HIV infection is associated with lep rosy and might reverse the epidemiological trend of the slow decline i n case notification in Tanzania if HIV infection is increasing greatly , Previous BCG vaccination loses its protection against leprosy in the presence of HIV infection. A repeated study is recommended in order t o validate these findings, whereby recording of the disability grading of the cases is necessary to adjust for delay in diagnosis.