Abstract
A study comparing the 48-h and 30-day reactions produced by three antigens was made in areas of low and high leprosy endemicity in Venezuela and in areas of Chile, a non-endemic country. The antigens used for the intradermal tests were standard Mitsuda antigen, supernatant from standard Mitsuda antigen, and PPD. The results indicate that there is no difference in the Mitsuda reaction of persons living in areas of high or low endemicity, but they show a statistically significant difference between the reactions in persons who live in endemic areas and those of persons living in a country where the disease has not been described. The difference in the Fernandez reaction obtained with the supernatant was not statistically significant between the two population groups in the endemic country, but was highly significant when comparing the endemic and the non-endemic countries.