What You Should Know About Leprosy

It was 1873, and Dr. Armauer Hansen of Norway had astounding news for the world: leprosy was caused by a bacterium (Mycobacterium leprae). Until then, the disease was thought to be derived from a curse or sinful behavior, frequently mentioned in the Bible.

The Leprosy Mission
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Leprosy, known as Hansen's Disease, still exists today. According to the World Health Organization (WHO), the global prevalence of leprosy at the beginning of 2014 was 180,000 chronic cases and over 215,000 new cases. Over 15 million people have been cured since treatments became available in the 1980s, but leprosy is still responsible for disfiguring or disabling more than 2 million people.


Modern medicine tells us that leprosy is spread when an untreated infected person coughs or sneezes, but not by sexual contact or pregnancy. However, leprosy is not very contagious. Approximately 95% of people have a natural immunity to the disease.

People with leprosy who are treated with medication do not need to be isolated from society. Due to misunderstanding the disease, in the past, people with leprosy were sent to 'leper colonies" on remote islands or in special hospitals.

Signs and Symptoms

The earliest sign of leprosy is commonly a spot on the skin that may be slightly redder, darker, or lighter than the person's normal skin. The spot may lose feeling and hair. In some people, the only sign is numbness in a finger or toe.

If left untreated, leprosy can progress to cause serious effects on the body, including:

  • Hands and feet - Leprosy bacteria attack the nerves in the hands and feet and cause them to become numb. A person may get cuts or burns on the numb parts and not know it, leading to infections that cause permanent damage. Fingers and toes may be lost to infection. Serious infections in the feet may require amputation. Paralysis may cause the fingers and toes to curl up permanently.
  • Eyes - Leprosy bacteria attack the nerves around the eyes, causing the loss of blinking reflex (which protects the eye from injury and moistens the surface). The eyes become dry and infected, and blindness may result. Because of the numbness of the eye, the person cannot feel debris in or scratches on the eye.
  • Face - Damage to the internal lining of the nose causes scarring and eventual collapse of the nose.


Leprosy is diagnosed by taking a skin sample (biopsy) and examining it under the microscope, looking for leprosy bacteria. Another test used for diagnosis is a skin smear. A small cut is made in the skin and a small amount of tissue fluid is taken. This is examined under a microscope for the presence of leprosy bacteria.


The good news is that leprosy is curable. In 1981, the WHO recommended the use of a combination of three antibiotics—usually dapsone, rifampin, and clofazimine—for treatment, which takes six months to a year or more. Certain cases may be treated with two antibiotics, but rifampin is a key component of either regimen. Since 1995, the WHO has provided these drugs free of charge to all leprosy patients worldwide.

During the course of treatment, the body may react to the dead bacteria with pain and swelling in the skin and nerves. This is treated with pain medication, prednisone or thalidomide (under special conditions).


Before treatment was available, a diagnosis of leprosy meant suffering and pain and being shunned by society. Today, antibiotics and good skincare will prevent the disease from destroying the body. Perhaps in the future, a vaccine will eliminate this ancient scourge altogether.

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  • World Health Organization. "Leprosy Today." Programmes and projects, 2015.