What type of disease is leprosy?

Leprosy also known as Hansen's disease is caused by the bacterium Mycobacterium leprae. 

It is highly contagious and can spread by coming in contact with the diseased person through his skin abrasions, nasal and throat discharges, etc. 

It is considered a chronic infection that affects the skin, mucous membranes, and nerves, and causes discolouration, and deformities in the skin.