The word “Leper” originates from a Greek word meaning scaly. It is one of the oldest diseases known to mankind. In India, leprosy has been known since ancient times as kushtha rog. The disease has always been stigmatized in India. Leprosy affects mainly the skin and peripheral nerves, although as it advances, organs such as the eyes, testes, bones and internal organs could also be affected.

More characteristically, it has the following features:

• Light skin patches with loss of sensation.
• Thickening of nerves.

As the disease progresses, there is a break down of the skin with the formation of ulcers, a likelihood of the hands and feet to be affected by trauma or burns, especially since they experience no sensation in the affected region. This results in deformities of the hands and face. Also, the nerve supply to muscles can be affected resulting in foot drop, claw toes etc. Thus, the disease does not kill but causes permanent and progressive physical disability including severe mutilation of the face and extremities, and widespread damage to the nerves, bones, eyes and vital organs. If a piece of skin or nerve is taken and examined, the organisms can be seen. The leprosy bacilli resist de–colorization when stained with acid fast stains (stains also used for staining the tuberculosis organisms). They usually occur in clumps and can be seen both inside and outside the cells. It is, however, difficult to grow these organisms outside the human body. This has made the development of vaccines difficult.

Sulfa drugs are used in the treatment of leprosy, and it has had a great impact on the treatment of the disease ever since it was first introduced in 1943. The National Leprosy Control Program was launched in 1955. It was later redevised in India in 1983 and called the National Leprosy Eradication Program.

The estimates for 1996 indicate that there are about 1.3 million cases of leprosy in the world. Over the last 10 years, the leprosy problem has been scaled down by about 83%. By the beginning of 1996, more than 90% of registered leprosy patients were being treated with MDT and, so far, about 8 million of them have been cured through this treatment.
Leprosy continues to be a problem in Third World countries. They account for 90% cases worldwide.

India
Leprosy still remains a major public health hazard in India. The country accounts for about one third of the leprosy cases in the world, and has by far the largest number of registered cases among individual countries. Due to migration, leprosy is increasingly being seen in urban areas in India.

The states/UTs that have the dubious distinction of a higher than national average are Orissa, Bihar, Jharkhand, West Bengal, Tamil Nadu, Nagaland, Assam, Madhya Pradesh and Daman and Diu.

Social stigma and leprosy
Leprosy is often referred to as a “Social Disease”. The social stigma attached to leprosy is due to the deformities it results in.

History of Leprosy
From the old records, it is evident that LEPROSY is a very ancient disease dating back many centuries. In India, leprosy was referred to as “KUSHTHA” in the ancient vedic literature as far back as 1400 B.C. The laws of Manu mention the instructions for the prevention of leprosy. A good description of this disease and its treatment is given in “SUSHRUTA SAMHITA” a book on surgery written in 600 B.C. by the eminent Indian surgeon SUSHRUTA. He regarded this disease as a contagious disease carried from a person suffering from this disease to a healthy person. There is strong evidence to show that leprosy was common as far back as 1400 B.C.

The word Leprosy is a translation of the Hebrew word “ZARAATH” and is mentioned in the Bible. The term included not only leprosy but also a number of other skin diseases. In ‘LEVITICUS’ clear instructions are given to the priests about the preventive measures against the spread of disease from persons suffering from leprosy. Some reference is made to Leprosy in Chinese literature dating back to 600 B.C. But there is no conclusive evidence to prove that it existed before.

The earliest description of the disease in Europe was given by Aractus a contemporary of Galen. Galen also referred to Leprosy as Elephantiasis Graecorum. Galen lived about A.D. 150. Hippocrates who lived in 450 B.C. did not mention Leprosy. The returning Greek and Roman armies probably introduced the disease into Europe. Prof. Moller Christensen through his studies of cranial bones found evidence of Leprosy in Great Britanin, France, and Egypt during the period A.D. 500-700. The disease was at its height in Europe between 1000 A.D and 1400A.D. Anderson in his thesis (1969) reviewed all the literature available about the spread and decline of Leprosy in Europe. The literature reveals that the authors believed Leprosy to be highly contagious. This known fact was probably responsible for the inhuman measures taken to contain the disease during that period.

During the 18th and early 19th century, before Hansen discovered the leprosy bacillus, the hereditary theory of leprosy became very popular in Europe. It was strongly supported by the Norwegian scientists but in view of the new epidemiological evidence in favour of the contagiousness of the disease, the hereditary theory lost its ground. Few authentic outbreaks of leprosy in Nuaru, Cape Breton, Louisiana and other places confirmed the contagiousness of the disease.

The patients during that time were confined in Lazar houses. Leprosy declined form this period and was completely eradicated during the 19th century in Europe due to: Isolation of the patients & Improvement of the socio-economic conditions in the continent, better housing, improved economic conditions, good nutrition, better sanitation have reduced the other factors responsible for the transmission of the disease.

Literature on the origin and spread of Leprosy in Africa is inadequate but the prevalence of disease in states like Nigeria, Uganda, Zaire was very high.

Leprosy was introduced into the Americas by the soldiers of Columbus first & later through the slave trade from the endemic areas of West Africa. Immigrants from Europe & China also introduced the disease into the continent.

The germ causing Leprosy is called Mycobacterium leprae and was discovered by G.H. Armauer Hansen (1841-1912) from Norway in 1873. Therefore, the organism is commonly known as Hansen’s bacillus.