In this preliminary report the histopathological appearance of the
lepromin reaction in armadillos was correlated with their response to
infection with M. leprae. Three different types of
lepromin response were described, namely the lepromatous, the borderline, and the tuberculoid
lepromin reactions. It was found that 10 out of the 11 animals with a lepromatous
lepromin reaction and the one animal with a borderline
lepromin reaction developed disseminated disease. The two with a tuberculoid
lepromin reaction and one of the 11 with a lepromatous
lepromin reaction failed to develop
leprosy. It is suggested that by using the
lepromin response it is possible to assess, to a great extent, the susceptibility of armadillos to
infection by M. laprae. The pros and cons of using the armadillo as an animal model for a
vaccine trial are briefly discussed.