What Is Leprosy
Key Facts from WHO
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Leprosy is a chronic infectious disease caused by a type of bacteria, Mycobacterium leprae.
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The disease predominantly affects the skin and peripheral nerves. Left untreated, the disease may cause progressive and permanent disabilities.
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The bacteria are transmitted via droplets from the nose and mouth during close and frequent contact with untreated cases.
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Leprosy is curable with multidrug therapy (MDT).
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Leprosy is reported from all the six WHO regions; the majority of annual new case detections are from South-East Asia Region
Background
Leprosy, also known as Hansen's disease, is a chronic infectious disease caused by the bacteria Mycobacterium leprae and Mycobacterium lepromatosis.
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M. leprae, one of the causative agents of leprosy. As an acid-fast bacterium,
M. leprae appears red when a Ziehl-Neelsen stain is used.
Transmission of leprosy occurs during close contact with those who are infected. Transmission of leprosy is through the upper respiratory tract. Whilst older research suggested the skin as the main route of transmission, more recent research has increasingly favoured the respiratory route whereby 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 described are the skin and the nasal mucosa, although their relative importance is not clear.
“The biggest disease today is not leprosy or tuberculosis, but rather the feeling of being unwanted”
Mother Teresa
