One of the challenges to eliminate leprosy as a public health problem is to know its real prevalence. This study compares the results of two published methods which propose to estimate the hidden prevalence of leprosy, the trends defined by the Ministry of Health and the estimate made by the State Secretary of Health of Mato Grosso (SES/MT) to implement the program "Tolerância Zero: Mato Grosso sem hanseníase" (Zero Tolerance: Mato Grosso Without Leprosy), based on the number of new cases detected in 2001. The methods and the trend were applied using the cases of leprosy detected in the period from 1996 to 2000 for all the municipalities of the state. The endemic level was defined as the arithmetic mean adjusted to the new cases detected in the same period. All estimates showed a positive association higher than 75% with the number of cases detected in 2001. The strongest association was obtained between the estimate of SES/MT (r²=0,895), which, in contrast, does not exclude the endemic level. We conclude that the published methods only suggest the presence of reservoirs of cases in areas with delayed detection. Operationally, it seems more adequate to rely on historical series according to age, operational classification, degree of physical incapacitation, and number of lesions at the time of diagnosis to identify the areas of risk and, consequently, eliminate leprosy.
Leprosy; Prevalence estimate; Mato Grosso
