Leprosy (from the
Greek lepi, meaning scales on a fish), or Hansen's disease (HD), is a
chronic disease caused by the
bacteria Mycobacterium leprae and
Mycobacterium lepromatosis.
[1][2] Leprosy is primarily a
granulomatous disease of the
peripheral nerves and
mucosa of the
upper respiratory tract; skin lesions are the primary external symptom.
[3] Left untreated, leprosy can be progressive, causing permanent damage to the skin, nerves, limbs and eyes. Leprosy does not directly cause body parts to fall off on their own accord;
[4] instead they become disfigured or autoamputated as a result of disease symptoms.
[5]Historically, leprosy has affected mankind for at least 4,000 years,
[6] and was well-recognized in the civilizations of
ancient China,
Egypt, and
India,
[7] but it is unknown if it is the same
disease mentioned in the
Hebrew Bible.
[8] In 1995, the
World Health Organization (WHO) estimated that between 2 and 3 million people were permanently disabled because of leprosy.
[9] In the past 20 years, 15 million people worldwide have been cured of leprosy.
[10] Although the forced
quarantine or segregation of patients is unnecessary in places where adequate treatments are available — and can be considered
unethical[
clarification needed][
citation needed] — many
leper colonies still remain around the world, in countries such as
India (where there are still more than 1,000 leper colonies),
[10] China,
[11] Romania,
[12] Egypt,
Nepal,
Somalia,
Liberia,
Vietnam,
[13] and
Japan.
[14] Leprosy was once believed to be highly contagious and sexually transmitted, and was treated with
mercury—all of which applied to
syphilis which was first described in 1530. It is now thought that many early cases of leprosy could have been syphilis.
[15] Leprosy is in fact neither sexually transmitted nor is it highly infectious after treatment, as approximately 95% of people are naturally immune
[16] and sufferers are no longer infectious after as little as 2 weeks of treatment. However, before treatment was developed, leprosy was certainly contagious.
[17][18]The age-old
social stigma associated with the advanced form of leprosy lingers in many areas, and remains a major obstacle to self-reporting and early treatment. Effective treatment for leprosy appeared in the late 1930s with the introduction of
dapsone and its derivatives. However, leprosy
bacilli resistant to dapsone soon
evolved and, due to overuse of dapsone, became widespread. It was not until the introduction of multidrug therapy (MDT) in the early 1980s that the disease could be diagnosed and treated successfully within the community.
[19]MDT for multibacillary leprosy consists of
rifampicin,
dapsone, and
clofazimine taken over 12 months. Dosages adjusted appropriately for children and adults are available in all
Primary Health Centres in the form of blister packages.
[19] Single dose MDT for single lesion leprosy consists of
rifampicin,
ofloxacin, and
minocycline. The move towards single dose treatment strategies has reduced the prevalence of disease in some regions since prevalence is dependent on duration of treatment.