Leprosy
Origin
Middle English lepruse, from leprous
Definitions
- 1: a chronic infectious disease caused by a mycobacterium (Mycobacterium leprae) affecting especially the skin and peripheral nerves and characterized by the formation of nodules or macules that enlarge and spread accompanied by loss of sensation with eventual paralysis, wasting of muscle, and production of deformities —called also Hansen's disease
- 2: a morally or spiritually harmful influence
Description
Leprosy or Hansen's disease (HD), is a chronic disease caused by the bacteria Mycobacterium leprae and Mycobacterium lepromatosis. Named after physician Gerhard Armauer Hansen, leprosy is primarily a granulomatous disease of the peripheral nerves and mucosa of the upper respiratory tract; skin lesions are the primary external sign. Left untreated, leprosy can be progressive, causing permanent damage to the skin, nerves, limbs and eyes. Contrary to folklore, leprosy does not cause body parts to fall off, although they can become numb or diseased as a result of infection; infection results in tissue loss, so fingers and toes become shortened and deformed as the cartilage is absorbed into the body.
Although the mode of transmission of Hansen's disease remains uncertain, most investigators think that M. leprae is usually spread from person to person in respiratory droplets. The minimum incubation period reported is as short as a few weeks and this is based on the very occasional occurrence of leprosy among young infants. The maximum incubation period reported is as long as 30 years, or over, as observed among war veterans known to have been exposed for short periods in endemic areas but otherwise living in non-endemic areas. It is generally agreed that the average incubation period is between three and five years. Leprosy is now known to be neither sexually transmitted nor highly infectious after treatment. Approximately 95% of people are naturally immune and sufferers are no longer infectious after as little as 2 weeks of treatment.
Leprosy has affected humanity for over 4,000 years, and was well-recognized in the civilizations of ancient China, Egypt, and India. DNA taken from the shrouded remains of a man discovered in a tomb next to the Old City of Jerusalem shows him to be the earliest human proven to have suffered from leprosy. In 1995, the World Health Organization (WHO) estimated that between 2 and 3 million people were permanently disabled because of leprosy at that time. In the past 20 years, 15 million people worldwide have been cured of leprosy. Although the forced quarantine or segregation of patients is unnecessary in places where adequate treatments are available, many leper colonies still remain around the world in countries such as India (where there are still more than 1,000 leper colonies), China, Romania, Egypt, Nepal, Somalia, Liberia, Vietnam, and Japan. 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.
The age-old social stigma, in other words, leprosy 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. 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.[20]
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. 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.[1]
