In the 20 years from 1994 to 2014, 16 million people worldwide were cured of leprosy. Separating people affected by leprosy by placing them in leper colonies is not supported by evidence but still occurs in some areas of India, China, Japan, Africa, and Thailand.

Leprosy has affected humanity for thousands of years. The disease takes its name from the Greek word lépra, from (lepís; 'scale'), while the term "Hansen's disease" is named after