HISTORY

Leprosy has existed for thousands of years, dating back to the earliest civilizations of China, Egypt and India. From as early as 600 B.C. there is evidence of Chaulmoogra Oil (a tree found in Eastern India) being used to ameliorate symptoms of the disease. Written accounts are common in ancient literature such as the Bible, and even earlier in Susrutha, regarded as the first Indian book on surgery, dating back to 400 B.C.

TREATMENT

After Hansen's discovery, it took science over 70 years for medicine to develop a cure in a drug known as Diamino Diphenyl Sulphone (Dapsone DDS). In 1946 Dr. Robert Cochrane successfully treated an Indian patient with the drug by an intramuscular injection. Though the use of Dapsone was effective in fighting Leprosy, further study showed that it had two disadvantages: 1) prolonged use can cause anemia, and 2) it does not actually kill the bacterium, but only stops its multiplication. Finally, the discovery of Dapsone-resistant bacteria heightened the need for a new drug. In the early 1960s two doctors experimenting in Nigeria found a drug named Clofazamine to be useful in treating lepromatous patients. While the drug has none of the disadvantages of Dapsone, it is classified as a dye and can lead to skin discoloration as well as ocular pigmentation.

While the advancement of science yielded the discovery of more effective medicines, it also revealed various forms of the disease. It was obvious that no one drug was totally effective against each variation. So in the 1970s medical facilities began employing a multi-drug therapy for many of the patients. Depending on the type of Leprosy and the progression of the disease within the patient, treatment is currently prescribed with a combination of several possible drugs. Some of these, such as Dapsone, Clofazamine and Thalidomide, may also be effective by themselves. Other drugs, like Rifampicin, Ofloxacin, Minocycline and Tetracycline, must be used in combination. After receiving treatment for three months, a Leprosy patient is normally considered non-infective to others.  The danger of that person spreading the disease becomes null, regardless of the stage of progression at which the disease was diagnosed and treatment was started. If the patient has developed deformities before treatment was started, those deformities can be corrected only by surgery. If the treatment is begun before deformities develop, the condition can be completed cured without leaving any visible evidence on the body.

BIOLOGY

The cause of Leprosy is a biological agent called Mycobacterium leprae. As indicated by the name, this bacterium resides in masses within the bodys lepra cells (in the lungs, the liver and the nervous system) during leprous inflammatory reactions. Leprosy manifests itself in two immunological stages: Multibacillary or Lepromatous Leprosy, which affects the skin and organs, is at the infectious end of the scale; and Paucibacilliary or Tuberculoid Leprosy, primarily affecting the nerves, is non-infectious. Within these two classifications, there are also several sub-classes, which facilitate diagnosis and treatment.

Generally, one or more of the following symptoms may characterize the disease:

• Hypo-pigmented patches
• Loss of sensation in the affected areas
• Nodules or lumps in the skin located on the face and/or ears
• Ulcers located on the soles of the feet
• Loss of digits
• Nasal depression
• Paralysis or severe weakness in the muscles of the foot (Foot-drop)
• Claw toes
• Loss of eyelashes (Madarosis)

TRANSMISSION

The exact method of transmission of Leprosy is not known. The M. Leprae bacterium exits the human body through the skin and the nose. While this is conclusive, its significance is unclear because the portal of entry into the human body remains unknown. Research indicates that the two most viable mechanisms of entrance are the skin and the upper respiratory tracts. However, other methods of transmission have not yet been ruled out.

Whatever the method of transmission, it is clear that individuals who are in close proximity with Leprosy patients have a heightened chance of contracting the disease. Of the different situations wherein proximity occurs (i.e. classroom, workplace, etc.), household proximity is the most easily identifiable and yields a risk of approximately four times higher than that of non-contacts.

A genetic component of the disease means that 95% of the general population is naturally immune to Leprosy. Those 5% who are susceptible must be in continuous and constant contact with a Leprosy patient to contract the disease.