Case detection, gender and disability in leprosy in Bangladesh: a trend analysis.

A trend analysis is presented of all newly detected leprosy cases over an 18-year period (1979-1996) in a highly leprosy endemic area of Bangladesh. A total of 23,678 new cases were registered, with an average of 860 new cases per year in the first 12 years, and increasing to around 3000 in 1996. The male:female (M:F) ratio decreased from 2.3 to 1.4. The proportions of newly detected cases with MB leprosy and of newly detected cases with any disability decreased over time. These reductions were more marked in the higher age groups of both sexes. The reduction in disability was primarily attributable to a decline in grade 2 disability. New case detection rates (NCDR) of all leprosy patients per 10,000 general population increased for males from 3 to 6; and for females from 1 to 4, while the NCDR of MB leprosy decreased in males from 1.4 to 0.6, and in females fluctuated around 0.45. The NCDRs of leprosy patients with disabilities showed an initial decrease in the first period, especially in males, but later showed an increase. The NCDR of males with disability was about twice as high as that of females. Finally, female NCDRs in the ages between 15 and 30 were low by comparison with the male NCDRs at the same time. This may be due to the sociocultural characteristics of the Bangladeshi society, with gender differences in exposure, health seeking behaviour and opportunities for case detection. Operational changes in the control programme have contributed to the changed profile of newly detected cases. This study shows that the application of general population statistics is essential for understanding the dynamics in leprosy control programmes under changing operational conditions. Combining case detection figures with such statistics helps to identify population groups that are possibly not benefiting sufficiently from the services provided, and to clarify the dynamics in control programmes and the future trends and programme requirements.