Fact sheet N°101
February 2010
Leprosy is a chronic infectious disease caused by Mycobacterium leprae, an acid-fast, rod-shaped bacillus. The disease mainly affects the skin, the peripheral nerves, mucosa of the upper respiratory tract and also the eyes, apart from some other structures.
Leprosy is curable and treatment provided in the early stages averts disability.
Multidrug therapy (MDT) treatment has been made available by WHO free of charge to all patients worldwide since 1995, and provides a simple yet highly effective cure for all types of leprosy.
The diagnosis and treatment of leprosy today is easy and most endemic countries are striving to fully integrate leprosy services into existing general health services. This is especially important for those under-served and marginalised communities most at risk from leprosy, often the poorest of the poor.
According to official reports received from 121 countries and territories, the global registered prevalence of leprosy at the beginning of 2009 stood at 213 036 cases, while the number of new cases detected during 2008 was 249 007. The number of new cases detected globally has fallen by 9126 (a 4% decrease) during 2008 compared with 2007.
Pockets of high endemicity still remain in some areas of Angola, Brazil, Central African Republic, Democratic Republic of Congo, India, Madagascar, Mozambique, Nepal, and the United Republic of Tanzania. These countries remain highly committed to eliminating the disease, and continue to intensify their leprosy control activities.
Leprosy was recognized in the ancient civilizations of China, Egypt and India. The first known written mention of leprosy is dated 600 BC. Throughout history, the afflicted have often been ostracized by their communities and families.
Although leprosy was treated differently in the past, the first breakthrough occurred in the 1940s with the development of the drug dapsone, which arrested the disease. But the duration of the treatment was many years, even a lifetime, making it difficult for patients to follow. In the 1960s, M. leprae started to develop resistance to dapsone, the world’s only known anti-leprosy drug at that time. In the early 1960s, Rifampicin and clofazimine, the other two components of MDT, were discovered.
In 1981, a World Health Organization (WHO) Study Group recommended multidrug therapy (MDT). MDT consists of 3 drugs: dapsone, rifampicin and clofazimine and this drug combination kills the pathogen and cures the patient.
Since 1995, WHO provides free MDT for all patients in the world, initially through the drug fund provided by the Nippon Foundation and since 2000, through the MDT donation provided by Novartis and the Novartis Foundation for Sustainable Development.
In 1991 WHO's governing body, the World Health Assembly (WHA) passed a resolution to eliminate leprosy as a public health problem by the year 2000. Elimination of leprosy as a public health problem is defined as a prevalence rate of less than one case per 10 000 persons. The target was achieved on time and the widespread use of MDT reduced the disease burden dramatically.
In order to reach all patients, treatment of leprosy needs to be fully integrated into general health services. This is a key to successful elimination of the disease. Moreover, political commitment needs to be sustained in countries where leprosy remains a public health problem. Partners in leprosy elimination also need to continue to ensure that human and financial resources are made available for the elimination of leprosy.
The age-old stigma associated with the disease remains an obstacle to self-reporting and early treatment. The image of leprosy has to be changed at the global, national and local levels. A new environment, in which patients will not hesitate to come forward for diagnosis and treatment at any health facility, must be created.
The following actions are part of the ongoing leprosy elimination campaign:
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