Sleeping sickness

Generally known as sleeping sickness, human African trypanosomiasis is a parasitic infection transmitted by tsetse flies that occurs in sub-Saharan Africa. In its latter stage, it attacks the central nervous system, causing severe neurological disorders and death if left untreated. More than 95 per cent of reported cases are caused by the parasite Trypanosoma brucei gambiense, which is found in western and central Africa. The other 5 per cent of cases are caused by Trypanosoma brucei rhodesiense, which is found in eastern and southern Africa. The reported number of new cases fell by 77 per cent between 1999 and 2014 (from around 28,000 to 3,700).

During the first stage, the disease is relatively easy to treat but difficult to diagnose, as symptoms such as fever and weakness are non-specific. The second stage begins when the parasite invades the central nervous system and the infected person begins to show neurological or psychiatric symptoms, such as poor coordination, confusion, convulsions and sleep disturbance. Accurate diagnosis of the illness requires a sample of spinal fluid.

Nifurtimox-eflornithine combination therapy or NECT, developed by MSF, Drugs for Neglected Diseases initiative (DNDi) and Epicentre, is now the World Health Organization recommended protocol. NECT is much safer than melarsoprol, the drug that was previously used to treat the disease, and which is a derivative of arsenic. Melarsoprol causes many side effects and can even kill the patient. It is hoped that the new molecules currently under clinical trial will lead to the development of a safe, effective treatment for both stages of the disease that can be administered orally.