Leprosy, also known as Hansen’s disease, is preventable and curable. In fact, 95% of the world population has natural immunity.

Credit: The Novartis Foundation/Tom Bradley

Leprosy is caused by Mycobacterium leprae and is transmitted via droplets through the nose and mouth of untreated persons affected by leprosy. After infection, it can take up to 20 years before symptoms begin to appear.

Since 1981, more than 16 million persons affected by leprosy have been treated with multi-drug therapy (MDT), donated at first by The Nippon Foundation, and since 2000 by Novartis, through the World Health Organization (WHO). Access to MDT has reduced the number of people being treated for M. leprae infection globally by 99%. However, the number of people newly diagnosed with leprosy has plateaued at more than 200,000 per year for over a decade. The majority of new leprosy diagnoses occur in Brazil, India, and Indonesia, where persons affected often delay medical attention due to limited access to health services or fear of stigma and discrimination.

Leprosy has medical and social implications, forcing people to abandon professions, lose sources of income, and limit access to health services. These implications affect individuals, families, and society as a whole.

Where is Leprosy Found? 

Communities are affected by leprosy across 150 countries, with most new diagnoses in Brazil, India, and Indonesia. This map from The Leprosy Mission shows the number of new diagnoses per country, based on data from WHO.

Leprosy and neglected tropical diseases

Leprosy is one of 19 neglected tropical diseases (NTDs) recognized by the WHO. Like other NTDs, leprosy is a disease of poverty. People who are affected by NTDs often face barriers to safe housing, nutritious food, health care, education, social services, and employment opportunities. These factors and more contribute to mental and emotional well-being challenges for people affected by NTDs. For the 5 million people who experience leprosy today, these challenges are further intensified by leprosy-related discrimination and stigma.

Disability and Stigma

Leprosy is curable with multi-drug therapy (MDT), and disability is preventable with an early diagnosis. However, the social stigma and discrimination that accompanies the disease often prevent people from accessing care. As a result, people who experience leprosy are often challenged with physical disabilities, poor mental and emotional well-being, and exclusion from their communities.

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