Some three decades ago, a mystery disease spread throughout Sudan and what is now South Sudan, decimating communities, sewing fear, and killing scores. It turned out to be kala azar, also known as visceral leishmanaisis, a disease that is spread by the bite of a sandfly and that is, as this episode showed, fatal if not treated.MSF began caring for kala azar patients during that epidemic and has continued to do so through the present day, in both Sudan and South Sudan, and in other East African nations where the disease appears, as well as in South Asia. The needs are different in the different locations, because the strains of the disease found have their own particular characteristics. What unites them, however, is that the people trying to combat the disease are hamstrung by shortcomings in targeted research and development that has resulted in a lack of suitable diagnostics and treatment regimens.There are 400,000 new cases of kala azar diagnosed worldwide each year with approximately 40,000 deaths due to the parasitic disease. The eight most affected countries – Bangladesh, Brazil, India, Ethiopia, Kenya, Nepal, Sudan, and South Sudan – represent over 90 percent of new cases.MSF has successfully adapted its treatment protocols over the years in order to bring shorter, less toxic, and less painful options to patients, but as VII Photo’s John Stanmeyer saw on a recent trip to MSF projects in South Sudan, a great deal remains to be done in order to provide better, more specialized, more accessible treatment and testing, and to prevent further devastation.