Visible Deformity after HD (Leprosy) Chemoprophylaxis among Tribal People in India: Quantitative Analysis of Data Extracted from Published Sources

This is a quantitative analysis of data concerning visible deformity among newly diagnosed Hansen’s disease - HD (leprosy) patients in Dadra Nagar Haveli, India, before and after the introduction of chemoprophylaxis. Chemoprophylaxis was introduced on 1 April 2015 and consisted of a rifampicin dose >10 mg/kg for contacts of nearly all “primary“ patients who were newly diagnosed from 1 April 2013 until 2017. The population had repeated door-to-door surveys in the two years before the introduction of chemoprophylaxis. Data was extracted from published sources. The variation in the annual number of newly diagnosed HD patients with visible deformity in this population in any given year was predictable to the extent of over 90% by the number of contacts in this population who had received chemoprophylaxis in the preceding year (p =.0002, R2 = 0.9132). The population incidence rate of newly detected visible HD deformity at HD diagnosis increased substantially, from 60/million population/yr in 2016, the year following the 2015 introduction of chemoprophylaxis. The evidence suggests that brief chemoprophylaxis among asymptomatic contacts of newly diagnosed HD patients was an important factor in the causation of visible deformity among newly diagnosed HD patients in this population. Biological plausibility is discussed. By contrast, the frequency of visible HD deformity typically declines between the start and end of full MDT treatment backed by a package of nerve function monitoring and holistic care. Consequently, it is recommended that the underlying biology of visible deformity after brief chemoprophylaxis be elucidated further by non-human experiments before exposing more people in endemic countries to the risks of brief chemoprophylaxis. This will help protect the limbs and eyes of family members and other contacts of persons who experience(d) HD.