Relapse rate in paucibacillary leprosy patients after multidrug therapy in North Arcot District

Surveillance data from 14,227 paucibacillary (PB) patients who had been released from treatment one year earlier, after completing multidrug therapy (PB regimen) for 6 to 12 months, were analysed to assess relapse rates and the influence of three variables, viz., number of lesions, nerve involvement and duration of treatment. The overall relapse rate at one year of surveillance was acceptably low at 0.34%. Relapse rates were about four times higher when there were many (4-9) lesions, or, when nerve was involved (0.80% cf 0.20%). Extending the duration of treatment beyond 6 months did not reduce the relapse rates significantly in the high risk groups. Detection of PB cases early, before these risk factors become operative, and treating them with MDT would appear to be the best strategy to minimize relapse rates.