Leprosy, also known as Hansen disease, is a bacterial infection affecting a person's skin, nasal lining, and peripheral nerves. This disease has prevailed across the globe but commonly affects the residents of warm tropical and subtropical regions. According to the World Health Organization (WHO), there are around 2,08,000 leprosy patients worldwide, mostly from Asia and Africa.
One of the oldest diseases existing since biblical times, leprosy was always considered a highly infectious and dangerous condition. Till date, many leprosy patients across the world are forced to live in isolation and suffer social stigma. This article will talk about the causes and symptoms of leprosy, its treatment, and eliminate misconceptions surrounding the disease.
What causes leprosy?
Leprosy is caused by Mycobacterium leprae (M. leprae) or Mycobacterium lepromatosis (M. lepromatosis) which affects the skin, eyes, respiratory tract and peripheral nerves of the infected person. Skin lesions appear mainly in the colder areas of the body. The disease can spread through cough or sneeze droplets from an infected person or direct contact with an untreated leprosy patient.
A person with a weaker immunity can get infected with the disease quickly. Children may be more susceptible to this disease than adults.
What are the types of leprosy?
There are several classifications of leprosy. The two main categories are the Ridley-Jopling classification and the World Health Organization (WHO) classification.
Ridley-Jopling classification identifies the following five gradations of the disease:
- Tuberculoid leprosy: Fewer lesions; some are large and numb with nerve enlargement
- Borderline tuberculoid leprosy: More but smaller lesions with more nerve enlargement
- Mid-borderline leprosy: Reddish plaques with moderate numbness and swollen lymph nodes
- Borderline lepromatous leprosy: Many lesions with raised bumps, plaques and more numbness
- Lepromatous leprosy: Several lesions, disfigurement, limb weakness and hair loss
The number of skin lesions defines world Health Organization (WHO) classification:
- The first form is paucibacillary; wherein there are fewer skin lesions with no bacterium seen on the skin smear.
- The second form is multibacillary; wherein there are multiple skin lesions with bacterium seen on the skin smear.
What are the symptoms of leprosy?
Leprosy doesn't show immediate symptoms. The infection gradually develops into the disease, and it may take between one to 20 years for the infected person to show the first signs of leprosy, which include:
- Skin lesions paler than the person's normal skin tone
- Skin lesions with reduced sensation
- Foot ulcers
- Dry and cracked skin
- Muscle weakness
- Numbness in the hands and feet
- Curled fingers
- Facial disfigurement
- Hair loss
- Dry eyes, ulcers and maybe blindness
Diagnosis of leprosy
The doctor will first examine the patient for physical signs of symptoms of leprosy. Based on this, the doctor will conduct a biopsy on a small skin sample. This may be followed by a skin smear test to identify paucibacillary or multibacillary leprosy.
The doctor may also conduct a lepromin skin test to diagnose the type of leprosy further. In this process, the patient is injected with a small dose of inactive leprosy-causing bacterium on the forearm. The skin patch will be observed after a few days. A patient infected with tuberculoid or borderline tuberculoid leprosy will show a reaction to the injection.
Treatment of leprosy
Leprosy can be cured if detected early. In 1995, the World Health Organization (WHO) introduced Multi-drug Therapy (MDT) to combat it. And this treatment is available for free across the world. Depending on the type of leprosy, the doctor may prescribe treatment for six months or longer, in case of severe leprosy. A combination of the following antibiotics is used for leprosy treatment:
- Dapsone (Aczone)
- Minocycline (Minocin)
- Ofloxacin (Ocuflux)
- Rifampin (Rifadin)
- Clofazimine (Lamprene)
For nerve damage, the doctor may prescribe anti-inflammatory medication such as prednisone (Rayos), aspirin (Bayer), or thalidomide (Thalomid). However, since thalidomide leads to a congenital disability, it should be avoided by pregnant women or women who plan to have a child soon.
Breaking the stigma
For decades, leprosy has been considered a highly contagious disease and the patients are banned from society. Many are denied employment opportunities and thus lead a life in financial struggles and emotional turmoil. The social stigma associated with the disease prevents patients from getting treatment at the right time.
In 1954, French humanitarian Raoul Follereau started the World Leprosy Day to honour Mahatma Gandhi's compassion towards leprosy patients. Across the world, the last Sunday of every January is observed as the World Leprosy Day to create awareness of leprosy. Besides, WHO has been working towards public awareness about leprosy and removing this social stigma.
However, leprosy is not highly contagious. The disease is transmitted through direct physical contact with an infected person. Sitting next to an infected person or shaking hands doesn't spread the disease. Also, the condition isn't transmitted from pregnant lady to her unborn child. Contrary to the misconception, animals like armadillos, chimpanzees and mangabey monkeys may rarely transmit the bacteria to humans.