Leprosy Q&A
1. What is leprosy?
Leprosy (also known as Hansen’s disease) is a complex, chronic neglected tropical disease caused by the Mycobacterium leprae bacterium. It affects the skin, the upper respiratory tract and peripheral nerves in the hands and feet, and eyes. Leprosy can affect anyone, at any age, but it is linked to poverty, malnutrition, and poor water, sanitation and hygiene.
2. How is leprosy transmitted?
It is thought that leprosy is transmitted via droplets from the respiratory tract combined with prolonged, close contact with infected individuals.
3. How is leprosy diagnosed?
Leprosy is difficult to diagnose at its early stages, but it often presents as numb patches on the skin. Currently, the most reliable method to diagnose leprosy, is a slit-skin-smear test in the laboratory. There is no field diagnostic.
The disease may incubate for up to twenty years before presenting with any signs. If leprosy remains undiagnosed, the person affected may unwillingly transmit the disease to family and friends and throughout a community.
However, within a short period of receiving Multidrug Therapy, a person with leprosy will no longer be infectious. If leprosy is diagnosed in its early stages, it can be treated readily, and it will not cause disabilities. Preventing disabilities from developing means people with leprosy are less likely to suffer from the stigma and discrimination that can destroy their livelihoods and entire lives.
4. How infectious is leprosy?
Leprosy is not very infectious. 95% of most populations have a natural immunity to leprosy. The remaining 5% become vulnerable, mainly through malnutrition, poor water, sanitation and hygiene and a compromised immune system. Leprosy is not hereditary.
5. Why are people with leprosy often so disfigured?
People with leprosy lose all feeling in the affected areas and as a result, there is diminished awareness of harm from trauma or heat. Without treatment, the lack of sensation can lead to permanent damage to skin, nerves, limbs, and eyes. It can also lead to the development of reoccurring, lifelong, hard-to-treat ulcers.
6. Is there a cure? How is leprosy treated?
Leprosy can be cured using Multidrug Therapy (MDT), which is made available at no cost to patients from the World Health Organization (WHO). If MDT is taken in the early stages of the disease, permanent damage to nerves and leprosy-related disability are completely avoided.
7. How many people are affected by leprosy in the world today?
In more recent years, the WHO statistics reveal that around 200,000 people are newly diagnosed with leprosy every year. Of great concern is that people with leprosy who have a late diagnosis, develop lifechanging, visible disabilities as a result.
These statistics do not account for those people who are who are not diagnosed and are unwillingly transmitting leprosy into their communities. In addition, the statistics do not include those individuals who have been treated for leprosy, but whose disabilities, caused by leprosy who have ongoing healthcare needs, or those who are subject to leprosy stigma and discrimination. It is thought that around four million people worldwide are affected by leprosy.
8. Which countries have leprosy, where is leprosy endemic?
184 countries and territories (out of a total of 221) worldwide reported data on leprosy to the WHO during 2023. *The WHO has identified 23 Global Priority countries for leprosy, where over 95% of the global total of people detected with leprosy are found. The 23 countries are: Angola, Bangladesh, Brazil, Comoros, Cote d'Ivoire, DR Congo, Egypt, Ethiopia, India, Indonesia, Kiribati, Madagascar, Micronesia, Mozambique, Myanmar, Nepal, Nigeria, Philippines, South Sudan, Sri Lanka, Sudan, Somalia, and Tanzania. Brazil, Indonesia and India between them account for nearly 80% of people with leprosy.
Last updated on 12 February 2025
Download Q&A
Leprosy (also known as Hansen’s disease) is a complex, chronic neglected tropical disease caused by the Mycobacterium leprae bacterium. It affects the skin, the upper respiratory tract and peripheral nerves in the hands and feet, and eyes. Leprosy can affect anyone, at any age, but it is linked to poverty, malnutrition, and poor water, sanitation and hygiene.
2. How is leprosy transmitted?
It is thought that leprosy is transmitted via droplets from the respiratory tract combined with prolonged, close contact with infected individuals.
3. How is leprosy diagnosed?
Leprosy is difficult to diagnose at its early stages, but it often presents as numb patches on the skin. Currently, the most reliable method to diagnose leprosy, is a slit-skin-smear test in the laboratory. There is no field diagnostic.
The disease may incubate for up to twenty years before presenting with any signs. If leprosy remains undiagnosed, the person affected may unwillingly transmit the disease to family and friends and throughout a community.
However, within a short period of receiving Multidrug Therapy, a person with leprosy will no longer be infectious. If leprosy is diagnosed in its early stages, it can be treated readily, and it will not cause disabilities. Preventing disabilities from developing means people with leprosy are less likely to suffer from the stigma and discrimination that can destroy their livelihoods and entire lives.
4. How infectious is leprosy?
Leprosy is not very infectious. 95% of most populations have a natural immunity to leprosy. The remaining 5% become vulnerable, mainly through malnutrition, poor water, sanitation and hygiene and a compromised immune system. Leprosy is not hereditary.
5. Why are people with leprosy often so disfigured?
People with leprosy lose all feeling in the affected areas and as a result, there is diminished awareness of harm from trauma or heat. Without treatment, the lack of sensation can lead to permanent damage to skin, nerves, limbs, and eyes. It can also lead to the development of reoccurring, lifelong, hard-to-treat ulcers.
6. Is there a cure? How is leprosy treated?
Leprosy can be cured using Multidrug Therapy (MDT), which is made available at no cost to patients from the World Health Organization (WHO). If MDT is taken in the early stages of the disease, permanent damage to nerves and leprosy-related disability are completely avoided.
7. How many people are affected by leprosy in the world today?
In more recent years, the WHO statistics reveal that around 200,000 people are newly diagnosed with leprosy every year. Of great concern is that people with leprosy who have a late diagnosis, develop lifechanging, visible disabilities as a result.
These statistics do not account for those people who are who are not diagnosed and are unwillingly transmitting leprosy into their communities. In addition, the statistics do not include those individuals who have been treated for leprosy, but whose disabilities, caused by leprosy who have ongoing healthcare needs, or those who are subject to leprosy stigma and discrimination. It is thought that around four million people worldwide are affected by leprosy.
8. Which countries have leprosy, where is leprosy endemic?
184 countries and territories (out of a total of 221) worldwide reported data on leprosy to the WHO during 2023. *The WHO has identified 23 Global Priority countries for leprosy, where over 95% of the global total of people detected with leprosy are found. The 23 countries are: Angola, Bangladesh, Brazil, Comoros, Cote d'Ivoire, DR Congo, Egypt, Ethiopia, India, Indonesia, Kiribati, Madagascar, Micronesia, Mozambique, Myanmar, Nepal, Nigeria, Philippines, South Sudan, Sri Lanka, Sudan, Somalia, and Tanzania. Brazil, Indonesia and India between them account for nearly 80% of people with leprosy.
Last updated on 12 February 2025
Download Q&A