Through years of concerted effort, leprosy has almost been eradicated - but there were still more than 200,000 new cases diagnosed in 2011.
Brazil, Indonesia, the Philippines, parts of Africa and India are the hardest hit by the disease. Leprosy is curable, but needs to be diagnosed before the nerve damage in the body becomes too severe.
OrangeLife, a medical laboratory in Rio de Janeiro, is pioneering a new test for leprosy which aims to be quick, accurate and above all cheap.
Al Jazeera's Gabriel Elizondo reports from Sao Paulo.