Leprosy, also known as Hansen’s disease, is a disease that predominantly affects the skin and the nerves which can cause significant disfigurement and disability. It is one of the oldest diseases known to man and continues to be a public health challenge in countries like India. According to the World Health Organization (WHO), around 184212 cases of leprosy were reported at the end of 2018 with a prevalence rate that corresponds to 0.2 cases per 10,000 people. India is one of the high-burden countries of leprosy with a prevalence rate of 1 per 10,000 people which indicates awareness about the condition.
Leprosy is surrounded by negative stigma which is the reason why many people think that this condition is a mutilating, contagious and incurable disease. In addition to numerous misconceptions, there is not much awareness about the causes, symptoms, diagnosis and treatment of the disease. So on the occasion of World Leprosy Day (which is observed every year on the last Sunday of January), let’s learn more about the condition.
What Are The Causes of Leprosy?
Leprosy is a chronic, progressive bacterial infection caused by a bacillus, Mycobacterium leprae (M. leprae). It is a slow-growing bacteria that can affect the skin, peripheral nerves, mucosal surfaces of the upper respiratory tract and the eyes.
It was once feared as a highly contagious and devastating disease, but now we know it doesn’t spread easily and treatment is very effective. However, if left untreated, the nerve damage can result in crippling of hands and feet, paralysis, and even blindness.
How Does Leprosy Spread?
Although the disease is not highly contagious, the bacterium can spread through the mucosal secretions of a person with the infection. So if a person with leprosy coughs or sneezes and a healthy person breathes in the droplets containing the bacteria, there is a high risk of getting infected. According to the Centres for disease control and prevention (CDC), only a prolonged and close contact with an individual with untreated leprosy over a long period can lead to an infection.
You do not catch leprosy from a casual contact with an infected person such as
– Shaking hands
– Sitting next to the person
– Eating with the person
– Talking to the person
Also, the disease is not spread from a mother to the baby during pregnancy. It doesn’t spread through sexual contact as well. So the best way to prevent it is to avoid close and long-term contact with a person suffering from the condition.
What Are The Symptoms Of Leprosy?
M. leprae is a slow-growing bacteria and this is the reason why it takes a long time to develop the symptoms. According to the World Health Organization (WHO), the disease has an average incubation period of 5 years. Incubation period is the time taken for the symptoms to appear after getting infected with a bacteria). In some cases, it may take as long as 20 years for the symptoms to appear. The bacteria affects the skin, nerves and the mucous membrane.
The common signs and symptoms of leprosy include:
-Skin sores and lesions (which appear as discolored patches of skin)
-Lumps or bumps on the skin that doesn’t even after few weeks
-Loss of sensation in the legs and arms
-Painful ulcers on the feet
-Painful swelling or lumps on the face
-Stuffy nose and or nose bleeds
If left untreated, the symptoms may turn aggressive which include
-Shortening of toes and fingers
-Non-healing ulcers on the feet
-Burning sensation of the skin
-Redness and pain around the affected area
-Loss of eyebrows or eyelashes
How is Leprosy Diagnosed?
Your doctor may suspect leprosy based on the appearance of the discolored skin patches (which appear either lighter or darker than the normal skin). In some cases the skin may become red and there might be loss of sensation. To confirm the diagnosis, your doctor may recommend a lab test to detect the presence of the bacteria in the skin or the nerve under a microscope. Other lab tests may also be recommended to rule other skin diseases (if any).
The WHO has categorized the disease depending upon the type and number of affected areas on the skin. These are:
Paucibacillary leprosy is when there are five or fewer skin lesions and the bacteria fails to show up in the skin sample.
Multibacillary leprosy is the condition in which there are more than five lesions and the bacteria can be detected in both blood and skin samples.
How Is Leprosy Treated?
As leprosy is a bacterial disease, it is treated with a combination of antibiotics for a period of over a year or two. Also, known as multidrug therapy, 2 – 3 antibiotics are prescribed to treat the condition. This therapy also helps to prevent the development of antibiotic resistance by the bacteria, which may further increase the course of treatment. The condition can be cured if the treatment is followed and completed as recommended by the doctor.
Antibiotics used to treat leprosy act by killing the bacteria and hence, can cure the disease and prevent it from getting worse. However, it does not reverse the nerve damage or any physical deformation that has occurred prior to the diagnosis of the condition. Hence, it is extremely important to diagnose the condition at the earliest to prevent permanent nerve damage.
(The article is reviewed by Dr. Swati Mishra, Medical Editor)