Leprosy does NOT affect axilla, groin and scalp because

(A) They are warmer regions of the body > Parts of the body that might be affected by leprosy are the cool areas, which can include superficial peripheral nerves, the anterior chamber of the eyes, the testes, the chin, malar eminences, earlobes, and knees. From this stage of leprosy, most lesions evolve into the tuberculoid, borderline, or lepromatous types