Leprosy - Causes, Types, Symptoms, Diagnosis & Treatment


Leprosy is a disease that causes severe, scarring skin sores and nerve damage in the limbs. This disease has affected people on every continent. Leprosy is actually not that infectious but it spreads when a healthy person comes in regular and close contact with mouse droplets and leprosy patient. Children get more affected by this disease than adults. Almost, 180000 people all over the world get infected with leprosy.

Cause of Leprosy

Mycobacterium leprae - Cause of Leprosy

This disease is caused by a bacteria, “Mycobacterium leprae” which is slow growing. Leprosy is also termed as Hansen’s disease after the name of the scientist – Dr. Gerhard Henrik Armauer Hansen who discovered this infectious disease in the year 1873.

Symptoms of Leprosy

Symptoms of Leprosy

Leprosy firstly affects the skin and then move on to nerves present outside the brain and spinal cord which is known as the peripheral nerves. Although, it takes three to five years for these symptoms to appear after coming in contact with the bacteria. In some cases, symptoms appear after 20 years of being infected. The time period between being exposed and the appearance of symptoms is known as the incubation period. If this period increases then, it is very difficult for doctors to diagnose the disease.

Types of Leprosy

There are six types of leprosy and are mainly based on the severity of symptoms.

  • Intermediate leprosy.

It is the earliest stage of leprosy. In this stage, patients suffer from flat lesions which may heal by themselves without progressing in case of strong immunity.

  • Tuberculoid leprosy

It is the mild and less serious type of leprosy. People suffering from this disease have some patches of flat and pale-colored skin and have no sensation on the affected area because of nerve damage. This is less infectious than other forms. This infection heals on its own, or it can persist and progress to a more severe form.

  • Borderline tuberculoid leprosy.

The symptoms at this stage are quite similar to the tuberculoid but the infections may be quite smaller and more in number which may continue and revert to tuberculoid, or to any other advanced form.

  • Mid-borderline leprosy

The sign and symptoms of this stage are quite similar to the Borderline tuberculoid leprosy. This includesreddish plaques with numbness which may regress or progress to another form.

  • Borderline leprosy

This type of leprosy is a cutaneous skin condition and the main symptoms include multiple wounds or scars including plaques, flat, raised bumps that may continue or regress.

  • Lepromatous leprosy

It is considered a more severe type of disease with many lesions with bacteria. The affected region is full of bumps, numbness, muscle weakness and rashes. Other symptoms include limb weakness, hair loss and other body parts such as kidneys, nose and male reproductive organs are also affected. It is more infectious than tuberculoid leprosy which never regresses.

Complications of leprosy

  • Blindness.
  • Kidney failure.
  • Muscle weakness.
  • Disfiguration of the face.
  • Infertility and Erectile dysfunction in men.
  • Permanent damage to the nerves within the brain.
  • Permanent damage to the nose from the inside resulting in nose bleeding.


Leprosy treatment fully depends on the type of leprosy the patient is suffering from. Antibiotics are used by doctors to treat the infection. Long-term treatment includes two or more antibiotics which will carry from 6 months to a year. People suffering from severe leprosy may need to take antibiotics for a longer time period. But, these antibiotics are unable to treat the nerve damage. There are some anti-inflammatory drugs that are used to control nerve pain and severe damage caused by leprosy.

For more detailed information about leprosy and other bacterial diseases, visit Byju’s

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A mixture containing equal quantities of germinating maize and groundnut seeds are taken. The RQ of this mixture would be _____.