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Why is leprosy difficult for most people to contract?

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Sign reading Gandhiji Prem Nivas Leprosy Centre Titagarh conducted by Missionaries of Charity, with a crucifix above the sign on a decorated building facade. — leprosy The Gandhiji Prem Nivas is a center for people with leprosy that was established by Mother Teresa in 1958 and is run by the Missionaries of Charity in Titagarh, India.

Leprosy is not highly infectious, and the primary reason it is difficult to contract is that the vast majority of people—approximately 95 percent—are naturally not susceptible to the Mycobacterium leprae bacillus. Even when individuals are repeatedly exposed to the bacteria, most will never develop the disease.1

Furthermore, for those who are susceptible, transmission typically requires prolonged, close contact with an infected person, such as within a family setting. While the bacillus can enter the body through the mucous membranes of the nose or through breaks in the skin, it does not spread through casual contact. In many cases where the infection is contracted, it is self-limiting and disappears before any symptoms become evident.213

It is important to note that the historical stigma surrounding this disease is scientifically unfounded; leprosy is entirely curable with modern drugs, and cured patients are no longer infectious. Treating individuals with dignity and rejecting the use of offensive, outdated terminology like "leper" is an essential ethical imperative in public health.2