Human African trypanosomiasis (sleeping sickness) occurs in sub-Saharan Africa. It is caused by the protozoan parasite Trypanosoma brucei, transmitted by tsetse flies.
With 12,000 cases of this disabling and fatal disease reported per year, trypanosomiasis belongs to the most neglected tropical diseases.
Life cycle of the Trypanosoma brucei parasites. Source: CDC, Wikipedia, public domain.
The clinical presentation is complex, and diagnosis and treatment difficult. The available drugs are old, complicated to administer, and can cause severe adverse reactions.
Imagine a disease that starts with a fly's bite and ends in death. The first stage of this disease causes non-specific symptoms such as itching and joint pains. If left untreated, it progresses to the second stage weeks, months, or even years later in which the affected person displays dramatic neurological and psychiatric symptoms before slipping into a fatal coma.
New diagnostic methods and safe and effective drugs are urgently needed. There is no field-friendly diagnostic test. Until recently, the most effective treatment for the second stage as almost as dangerous as the disease.
Vector control, to reduce the number of flies in existing foci, needs to be organised on a pan-African basis.
References:
[Seminar] Human African trypanosomiasis. Reto Brun, Johannes Blum, Francois Chappuis, Christian Burri. The Lancet, Jan 2010.
Killer coma: the evolving story of sleeping sickness treatment. The Lancet, Volume 375, Issue 9709, Page 93, 9 January 2010.