What is Leprosy?

Leprosy is an infectious disease caused by the bacterium Mycobacterium leprae. Usually called Hansen’s Disease, leprosy can cause nerve damage and affect the skin and extremities. It can spread between people through nasal secretions and in the air through coughing and sneezing, as well as through hand-to-hand contact. Fortunately, most people are naturally immune to the bacterium that causes leprosy.

A disease similar to modern-day leprosy has been around for thousands of years. Once it was considered a slow and painful death sentence, but in modern times it is easily treated with antibiotics.

Because leprosy impacts the nerves, sufferers lose feeling in their extremities. That inability to feel their fingers, toes, noses, etc., can lead to those body parts getting easily injured or infected.

What are the Symptoms of Leprosy?

In the early stages of leprosy, you may see spots on your skin that are slightly light or dark. Eventually, the spots become numb and you lose any hair on the affected skin. Other patients don’t have spots, but may feel numbness in their fingers or toes. These symptoms increase in severity very gradually, over the course of 2 to 10 years.

Advanced leprosy causes muscle paralysis. Your hands may curl unnaturally and you may lose the ability to blink. Nerves in your legs stop working and you don’t feel your feet. These issues can lead to the loss of extremities, blindness and deformity.

Leprosy Causes

Leprosy is caused by an infection of a bacteria called Mycobacterium leprae. Since this bacteria tends to grow very slowly, it is often difficult to find the source of it and establish exactly how the infection occurred. However, contrary to popular belief, leprosy is not a highly infectious disease.

Most of the time, leprosy is contracted by prolonged, close contact with someone else with the disease who has not had any treatment. Shaking hands with someone or sitting next to them for a short period of time will not result in you contracting the infection.

Instead, it’s believed that the bacteria is spread through water droplets from a contaminated person. For example, if an infected person coughs or sneezes and someone breathes in the droplets from the cough or sneeze, they may develop the disease themselves. However, it appears that repeated exposure of this kind is necessary to contract leprosy.

Armadillos are naturally infected with Mycobacterium leprae, so it is possible that people can contract leprosy from these animals. However, the vast majority of people who come into contact with them will not develop leprosy.

How is Leprosy Treated?

Leprosy can be treated through a long-term course of antibiotics. Your doctor may have you take a combination of antibiotics for a period of 6 months to 2 years to ensure the bacteria are completely gone from your body.

There are often no remaining issues after leprosy has been treated. However, if you had already begun to feel numbness before you received treatment, you may have permanent nerve damage.

Leprosy Prevention

In the US, leprosy is very rare. Regions in Africa and Asia tend to have the most outbreaks of leprosy but even there the disease is relatively uncommon. Around 95% of people around the world are immune to leprosy, so for Americans there is little use in trying to prevent leprosy since the chances of getting it are so slim.

In the very rare instance that leprosy is contracted, it’s important to seek treatment as soon as possible. Once treatment has begun, patients become noninfectious and should not pass it on to other people. Plus, the sooner treatment begins, the less likely it is for long term complications and disabilities to occur.

Last Reviewed:
October 09, 2016
Last Updated:
March 27, 2019