Causes of Leprosy

The causes of leprosy are directly linked to the bacteria Mycobacterium leprae. The bacteria is thought to be spread from person to person primarily through infected droplets. However, more than half of those with the disease have no confirmed contact with an infected person. Other factors that may play a role in the causes of leprosy include genetics, the extent of exposure, and environmental conditions.

Leprosy Information

Causes of Leprosy: An Overview

Causes of leprosy can be linked to an infection with the bacteria Mycobacterium leprae.

Causes of Leprosy: Mycobacterium Leprae

Mycobacterium leprae are part of the family Mycobacteriaceae. This is the same family as the bacteria that cause tuberculosis (Mycobacterium tuberculosis). Mycobacterium leprae grow slowly and mainly affect the:

Skin
Nerves
Mucous membranes.

Even in severe cases of leprosy, the destruction caused by Mycobacterium leprae is limited to the:

Peripheral nerves
Skin
Upper respiratory passages
Front portion of the eyes
Hands
Testes
Feet.

Most scientists believe that leprosy spreads from person to person through infected respiratory droplets. While this may be one mode of leprosy transmission, over half of the people who develop the disease have no confirmed contact with an infected person. Other factors that may play a role in a person developing leprosy include:

Genetics
The extent of exposure
Environmental conditions.

When a person becomes infected with Mycobacterium leprae, the bacteria begin to multiply within the body. After three to five years, leprosy symptoms can appear. This period between becoming infected and the start of symptoms is the "leprosy incubation period." Although the incubation period for leprosy is typically between three and five years, it can range from six months to several decades.

(Click Leprosy Symptoms for a list of symptoms associated with this disease.)