We describe a further simplification of a dipstick assay for the detection of antibodies to phenolic glycolipid I of Mycobacterium leprae by using whole blood and evaluated the assay performance in the leprosy endemic area of Amazonas in Brazil. The agreement with the 'gold' standard ELISA was 94.9% (kappa value = 0.87). This simple assay may be useful to identify those at risk of developing leprosy, for example among contacts of leprosy patients at lower levels in the health services.