Leprosy is a chronic mycobacterial infection that produces mucocutaneous lesions and peripheral nerve damage, resulting in neurologic dysfunction, disability, deformity, and limb loss. Two mycobacterial species are responsible for causing leprosy: Mycobacterium leprae and Mycobacterium lepromatosis. There are existing gaps in our understanding of leprosy transmission. Still, sufficient evidence suggests that the infection is transmitted from person to person from those with multibacillary leprosy, as a zoonosis, and potentially from environmental sources such as soil and water. In modern times, leprosy predominantly affects poor and underserved individuals who endure the lowest human development indices and who often suffer stigma, neurologic disability, and premature death. Social improvements for marginalized populations predominantly affected by this chronic infectious disease are crucial. A better understanding of the social origins of leprosy and possible animal or environmental reservoirs may explain the persistent global incidence of leprosy and inform the development of effective interventions to reduce infection transmission and facilitate early diagnosis of new cases, thereby preventing neurologic disability and sequelae.