The disease is endemic in some regions of sub-Saharan Africa, covering areas in about 37 countries containing more than 60 million people. It is estimated that 50,000 to 70,000 people are currently infected, the number having declined somewhat in recent years. The number of reported cases was below 10,000 in 2009, the first time in 50 years.It was believed that many cases go unreported. About 48,000 people died of it in 2008.Four major epidemics have occurred in recent history: one from 1896–1906 primarily in Uganda and the Congo Basin, two epidemics in 1920 and 1970 in several African countries, and a recent 2008 epidemic in Uganda.

source: wikipedia