RESUMO
The epidemiometric model of leprosy, built on Polambakkam, India, data, is used to compare the impact on incidence of dapsone and different multidrug therapy (MDT) strategies. The simulations show that generalization of MDT could have a dramatic impact on transmission of the disease. Relapses after MDT, although important from an individual point of view, have a negligible influence on the incidence. Introduction of MDT requires investments that, during the first few years of the program, are much greater than for dapsone monotherapy. These are, however, rapidly absorbed due to the rapidly declining number of new cases, particularly when MDT is not limited to multibacillary cases but is administered to all patients.
Assuntos
Simulação por Computador , Dapsona/uso terapêutico , Hansenostáticos/uso terapêutico , Hanseníase/tratamento farmacológico , Análise Custo-Benefício , Quimioterapia Combinada , Humanos , Incidência , Hanseníase/epidemiologiaRESUMO
Of the 47,068 patients registered in the Polambakkam Leprosy Center between 1955 and 1982, we selected 1886 cases having shown bacteriological positivity at any time during this period, whatever their classifications at registration, and subsequently found bacteriologically negative. After an average follow-up period of 10 years, 243 relapses were observed, giving a crude relapse rate of 12.8 per person-years of observation and a cumulative probability of relapse of 18.9%. Relapse rates were found to be dependent on regularity during smear-positive and -negative periods; a regularity greater than 75% in the smear-positive period proved to be particularly important. The results show no evidence that relapses occurring after 3 years of negativity could be reinfections, and that the relapse rate was still affected by regularity 7 years after negativation. The median delay of relapses was found to be 4.4 years and was not affected by the regularity of treatment.
