Leprosy is an infectious disease, the development and clinical progres
sion of which depend on the host immunological behavior. In this revie
w we describe the general features of leprosy and review the current k
nowledge on immunology. In particular, this article focuses on the fea
tures of the host-parasite interaction and the manner of adaptation of
Mycobacterium leprae to the host environment, an understanding of whi
ch provides an insight into the pathogenesis of leprosy.