Leprosy, also called Hansen's disease, is an infectious disease that is characterized by disfiguring skin sores and progressive nerve damage. Armauer Hansen discovered the disease-causing bacteria in 1873.
There are two types of leprosy: tuberculoid and lepromatous. Both forms cause skin sores and peripheral nerve damage, but lepromatous is more severe. It causes large, disfiguring lumps and bumps (nodules) on the skin. Only the lepromatous form is considered contagious.
Researchers estimate that more than one million people worldwide have leprosy. It is most common in Asia (especially Nepal and India), Latin America, and Africa. An estimated 4,000-6,000 Americans have leprosy. Nearly all cases of leprosy in the United States occur in patients who emigrated from developing countries. Leprosy is more common in developing countries because these areas are more likely to be unsanitary and highly populated.
According to the World Health Organization (WHO), access to information, diagnostic procedures, and treatment have helped decrease the prevalence of leprosy worldwide. Since 1985, 113 countries out of the 122 countries where leprosy was a public health concern have eliminated the disease. Since 2001, the number of new leprosy cases has decreased by 20% each year.
Individuals can develop leprosy at any age. However, it is most common among patients who are in their 20s and 30s. The severity of leprosy does not vary with age.
Individuals can become infected with either form of leprosy after coming into contact with Mycobacterium leprae when they are exposed to contaminated soil or armadillos that carry the bacteria. However, researchers have not discovered exactly how the disease spreads from person to person. It was initially believed that the disease was transmitted after physical contact with an infected individual. However, experts currently believe that the lepromatous form of leprosy is passed from person to person through expelled droplets from the mouth and nose of an infected person. Experts believe that most cases are spread after close, long-term contact with an infected individual. According to this new theory, individuals who inhale these droplets may become infected.
Leprosy is not considered a highly contagious illness. About 95% of people who are exposed to the bacteria that causes leprosy do not develop the disease. Healthcare workers often treat people with leprosy for many years without contracting the disease.
A combination of medications, called antibiotics, is used to kill the bacterium that causes leprosy. These medications cure the disease and prevent it from progressing, but they do not reverse nerve damage or physical disfiguration. Therefore, it is important to visit a healthcare provider as soon as symptoms develop.

Related Terms

Antibiotics, bacteria, bacterial infection, bacterium, clofazimine, dapsone, Hansen's disease, immune response, leper, lepromatous, lepromatous leprosy, lepromin skin test, MDT, multidrug therapy, Mycobacterium leprae, nerve damage, nodules, peripheral nerve damage, peripheral nerves, tuberculoid, tuberculoid leprosy, reconstructive surgery, rifampin.