Leprosy, also known as Hansen’s Disease, is a chronic infectious disease caused by the bacterium Mycobacterium leprae.

Leprosy is an ancient disease that has afflicted humans since before 300 BC. Recorded instances of Leprosy have been found in ancient texts from China, Egypt, and India, among others.

Contrary to popular belief, Leprosy does not cause body parts, such as fingers, toes, etc, to simply fall off. Since ancient times, Leprosy has had a serious social stigma attached to it, where sufferers are treated as outcasts and believed to be “unclean” or “cursed by God”, and this stigma still lingers in many areas of the world today. This stigma prevents many people from seeking help or treatment when they contract the disease. Instead, they hide away until their symptoms are so severe that their condition is finally discovered. By then, irrecoverable damage may have been caused.

Many people also believe that the Leprosy is highly contagious and incurable, but both of these myths are false.

The forced quarantine and segregation of Leprosy sufferers is not necessary. However, Leper Colonies still exist even in todays modern world, especially in countries like India and Vietnam and even in China.

In 1995, the World Health Organization (WHO) estimated that between two and three million individuals were permanently disabled because of Leprosy.

There are three types of Leprosy:

• Borderline Leprosy • Multibacillary Hansen’s Disease, or Lepromatous Leprosy • Paucibacillary or Tuberculoid Leprosy

And each have slightly different symptoms, and differing types and patterns of skin lesions. In addition to humans, only armadillos and several species of monkeys (namely chimpanzees, mangabeys, and macaques) are known to be able to contract Leprosy.

Leprosy Symptoms

Contrary to popular belief, Leprosy does not cause body parts, such as fingers, toes, etc, to simply fall off. While Leprosy affects the skin, nerves, and mucous membranes, the primary symptoms are:

• Loss of sensation and lack of pain in the limb extremities, for example when injury occurs to a limb • Skin lesions, nodules, plaques, thickened dermis, pigmented skin, and similar • Weakness

The loss of sensitivity in the limb extremities is why even small wounds can lead to undetected deterioration of the tissues. The lack of pain in the limb extremities compounds the problems because the person does not know they are injured.

If left untreated, Leprosy can cause progressive and permanent damage to the skin, nerves, limbs, and eyes.


Leprosy, also known as Hansen’s Disease, is a chronic infectious disease caused by the bacterium Mycobacterium leprae (M. leprae).


Leprosy may be transmitted to humans, and between humans, in the following ways:

• Respiratory droplets emitted by an infected person and breathed in by another. • Entry into the blood stream through broken skin.

It is believed that a person may be infected with Mycobacterium leprae bacteria for anything from a few months to 30 years or so before they display any symptoms of Leprosy. The average period of time between infection and symptoms is believed to be between 3 and 5 years.

Not all people infected with Mycobacterium leprae develop leprosy. Clearly, some people have increased resistance or immunity, and a range of factors may contribute to this resistance, such as genetic factors, nutrition, and exposure to other prior bacteria and diseases.

One month after infected people begin treatment with MDT they are no longer infectious.


The first effective treatment for Leprosy appeared in the late 1940s, with the development and introduction of Dapsone and its derivatives Rifampin and Clofazimine. However, the bacterium that causes Leprosy, Mycobacterium leprae, became resistant to these medications over time, severely reducing their effectiveness.

In the 1980s, a new Multidrug Therapy (MDT) was developed and introduced, which is a combination of Dapsone, Clofazimine, Rifampicin. This treatment remains effective to this day, because the Mycobacterium leprae bacteria have not been able to become resistant to this combination of drugs.

The MDT treatment is quite expensive, because the medications need to be taken for between 6 months and 2 years, depending on the type of Leprosy.

Prevention and Control

Avoiding the risk of contracting Leprosy is simply a matter of avoiding exposure to the Mycobacterium leprae bacteria or those infected with Mycobacterium leprae, especially avoiding breathing the bacteria in or allowing it to enter skin wounds.

In 1991, the 44th World Health Assembly (WHA) resolved to eliminate leprosy as a public health problem by the year 2000. To make this occur, the World Health Organization (WHO) is supplying endemic countries with free MDT treatment packs until at least 2010.

For future updates, subscribe via Newsletter here or Twitter