Why does kino compare himself to leprosy?

Kino compares himself to leprosy to illustrate the destructive and isolating effects of his newfound wealth and ambition. Just as leprosy is a disease that alienates and dehumanizes those who suffer from it, Kino feels that his pursuit of the pearl and the dreams it represents has begun to corrupt his relationships and sense of self. This comparison underscores the idea that material desire can lead to suffering and social isolation, transforming him from a simple man into someone marked by conflict and despair.