Epidemiological profile of leprosy cases at Nazareti Leprosy Center, Tanzania: A retrospective analysis (2000–2024)

Introduction Leprosy, also commonly known as Hansen’s Disease (HD) remains a neglected tropical disease and a public health concern in disease endemic regions of the world. However, significant progress in disease reduction has been achieved in recent years through multidrug therapy programs, implemented by the World Health Organization (WHO). This study assessed the trend and epidemiological profile of HD cases diagnosed at Nazareti Leprosy Center (NLC), Ifakara, Tanzania, over a 25-year period. Methods A retrospective cross-sectional study was conducted using routinely collected clinical records of newly diagnosed HD cases registered at NLC between 2000 and 2024. Data on demographic characteristics, clinical classification of HD, operational categories (paucibacillary and multibacillary), and disability grades of patients at presentation were collected. Poisson regression estimated annual incidence trends as incidence rate ratios (IRRs), while logistic regression assessed changes in leprosy characteristics as odds ratios (ORs), both reported with 95% confidence intervals (CIs). Results A total of 801 HD cases were recorded, of which males accounted for 67.4% of cases, with the highest proportion occurring among individuals aged 50 + years (33.2%). Multibacillary disease predominated (62.7%), while grade 1 disability (G1D), at diagnosis was more common (52.7%) than G2D. Overall, case notifications increased significantly over time, with an average annual rise of 4.0% (IRR = 1.04; 95% CI: 1.03–1.07; p < 0.001). Significant increases were observed among male individuals aged ≥50 years. Multibacillary HD cases and G1D disability also increased. In contrast, childhood cases (0–14 years) declined significantly during the study period. Conclusions Leprosy epidemiology in rural Tanzania shows evolving patterns characterized by increasing case detection, a rising burden of multibacillary disease, and disability at diagnosis, versus a decline in childhood cases over time. Intensifying early case detection, community awareness, treatment and surveillance are essential to eliminate HD as a public health concern.