respiratory route. Transmission occurs through inhalation of bacilli present in upper airway secretion.

Leprosy is not sexually transmitted and is not spread through pregnancy to the unborn child. The majority (95%) of people who are exposed to M. leprae do not develop leprosy; casual contact such as shaking hands and sitting next to someone with leprosy does not lead to transmission. People are considered non-infectious 72 hours after starting appropriate multi-drug therapy. Two exit routes of M. leprae from the human body that are often