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Cattle movements are helping one of the parasites spread, say the researchers

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Scientists have warned that Uganda faces major problems dealing with sleeping sickness if two forms of the parasite that cause the disease are brought together by cattle movements.

The best ways of diagnosing or treating sleeping sickness are only effective for one or the other form. Due to the geographical locations of each, this has not yet been a problem in Uganda.

But a study in the British Medical Journal last week (26 November) shows that uncontrolled movements of cattle — which carry the parasite — are moving the eastern form northwards.

Only 150 kilometres now separate them.

The researchers warn that unless action is taken, the two forms will soon meet, leaving Uganda's health authorities struggling to diagnose and treat the disease correctly.

Sleeping sickness kills about 100,000 people a year. The disease's acute form is caused by the parasite Trypanosome brucei rhodesiense in East Africa. A related form, Trypanosome brucei gambiense, causes chronic illness and is found in West and Central Africa.

The research team, led by Susan Welburn of the University of Edinburgh, UK say that the area of Uganda affected by the acute (eastern) form has increased by two and a half times since 1985.

They say it is "a matter of urgency" that international funding is used to set up a laboratory and train staff because of the "continent-wide importance" of the two forms overlapping.

The researchers are urging widespread treatment of livestock to kill the parasites, which are transferred to people via the bites of tsetse flies. They add that existing rules that prevent livestock being sold without prior treatment must be enforced more rigorously.

Link to paper in the British Medical Journal

Reference: British Medical Journal 331, 1238 (2005)