Use of modified Ridley's bacteriological scale for assessment of multibacillary leprosy cases under multidrug therapy

Abstract

In order to obtain proper judgement of bacterial quantum in human source (leprosy cases) a modification to Ridley's Bacteriological Index is suggested by applying formula as follows : Average Bacteriological Index of the group of patients X No. of patients in group X "scoring point" based on Ridley`s logarithmic Bacteriological Index scale.This new system based on arithmetic scale has been applied to multibacillary leprosy cases under multidrug therapy in leprosy colonies and leprosy control unit in an urban area. This comparison revealed that the introduction of multidrug therapy initiated a reduction in total bacteriological quantum very fast (i.e.) 100% to 5% at 12 months, 2.5% at 24 months in leprosy colonies where there was no entry of multibacillary case. However, in the urban slum there is an influx of new multibacillary cases every year, though bacterial quantum reduced as compared to initial status, it has remained static even at 60th month. The application of modified Ridley's Bacteriological scale to judge "total bacterial quantum : in any given control area gives a more realistic indication of the progress of MDT programme.