Leprosy, also known as Hansen's disease (HD), is a long-term infection by the bacteria Mycobacterium leprae or Mycobacterium lepromatosis. Initially, infections are without symptoms and typically remain this way for 5 to 20 years. Symptoms that develop include granulomas of the nerves, respiratory tract, skin, and eyes. This may result in a lack of ability to feel pain, thus loss of parts of extremities due to repeated injuries or infection due to unnoticed wounds. Weakness and poor eyesight may also be present.

Leprosy is spread between people. This is thought to occur through a cough or contact with fluid from the nose of an infected person. Leprosy occurs more commonly among those living in poverty. Contrary to popular belief, it is not highly contagious. The two main types of disease are based on the number of bacteria present: paucibacillary and multibacillary. The two types are differentiated by the number of poorly pigmented, numb skin patches present, with paucibacillary having five or fewer and multibacillary having more than five. The diagnosis is confirmed by finding acid-fast bacilli in a biopsy of the skin or by detecting the DNA using polymerase chain reaction.

Leprosy is curable with a treatment known as multidrug therapy. Treatment for paucibacillary leprosy is with the medications dapsone and rifampicin for six months. Treatment for multibacillary leprosy consists of rifampicin, dapsone, and clofazimine for 12 months. A number of other antibiotics may also be used. These treatments are provided free of charge by the World Health Organization. Globally in 2012, the number of chronic cases of leprosy was 189,000, down from some 5.2 million in the 1980s. The number of new cases was 230,000. Most new cases occur in 16 countries, with India accounting for more than half. In the past 20 years, 16 million people worldwide have been cured of leprosy. About 200 cases are reported per year in the United States.

Leprosy has affected humanity for thousands of years. The disease takes its name from the Latin word lepra, which means "scaly", while the term "Hansen's disease" is named after the physician Gerhard Armauer Hansen. Separating people by placing them in leper colonies still occurs in places such as India, China, and Africa. However, most colonies have closed, since leprosy is not very contagious. Social stigma has been associated with leprosy for much of history, which continues to be a barrier to self-reporting and early treatment. Some consider the word "leper" offensive, preferring the phrase "person affected with leprosy". World Leprosy Day was started in 1954 to draw awareness to those affected by leprosy.

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Leprosy

Progress in leprosy research
Recently, three new drugs, namely, ofloxacin-a fluoroquinolone, clarithromycin-a macrolide and minocycline -a tetracycline, all acting by different mechanisms, have shown very promising antileprosy activity in experimental models and short-term clinical trials. These drugs offer the potential for increasing the effectiveness and shortening the duration of antileprosy chemotherapy. In addition, new drugs may prove useful against Mycobacterium leprae strains resistant to the drugs currently in use, especially the strains resistant to rifampicin.
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Recent Advancement in the Diagnosis and Treatment of Leprosy.
Abstract
BACKGROUND : Many of the tropical diseases are neglected by the researchers and medicinal companies due to lack of profit and other interests. The Drugs for Neglected Diseases initiative (DNDi) is established to overcome the problems associated with these neglected diseases. According to a report published by the WHO, leprosy (Hansen's disease) is also a neglected infectious disease.
METHODS : A negligible amount of advancements has been made in last few decades which includes the tools of diagnosis, causes, treatment, and genetic studies of the bacterium (Mycobacterium leprae) that causes leprosy. The diagnosis of leprosy at earlier stages is important for its effective treatment. Recent studies on vitamin D and its receptors make leprosy diagnosis easier at earlier stages. Skin biopsies and qPCR are the other tools to identify the disease at its initial stages.
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Promising new leprosy vaccine moves into human trials
Today marks a significant step forward in the prevention and treatment of leprosy as the Infectious Disease Research Institute (IDRI) and American Leprosy Missions announce the start of a Phase 1 clinical trial in humans for a promising leprosy vaccine candidate—the first vaccine developed specifically for leprosy.
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