In 1995, a WHO Expert Committee estimated that 60 million people were at risk with an estimated 300 000 new cases per year in Africa, and fewer than 30,000 cases diagnosed and treated. In 2004, the number of new reported cases fell to 17 616 and WHO considered this due to increased control, estimating the total annual cases to be between 50 000 and 70 000 cases. In 2009, the number of new cases reported dropped below 10 000 (9 878) for the first time in 50 years and the estimated number of actual cases was 30 000. This plummeting trend continued and in 2014 only 3 796 cases were reported with less than 15 000 estimated cases.
In February 2008, WHO launched the initiative of the Atlas of HAT to map at village level all reported cases during the period 2000–2009. This initiative is jointly implemented with FAO within the PAAT framework. The process is ongoing and includes the 25 countries having reported at least one case in the last ten years. The Atlas is built from a database including geographical and not published epidemiological data), compiled by WHO through the contribution of SSNCPs, NGOs and Research Institutes.
Based on information on the HAT reported cases and the geographic distribution of human population, spatially explicit estimates of population at risk have been calculated and classified in five categories of risk, ranging from “very high” to “very low”. Approximately 70 million people are estimated to be at different levels of risk of contracting HAT in Africa.