Human African trypanosomiasis

The history of sleeping sickness


By the end of the sixties the majority of countries in the tsetse belt became independent. Health services were facing severe budgetary and operational constraints and after so many years of sustained low endemicity the priority of trypanosomiasis control was no longer the untouchable number one. The mobile team programmes with their privileged autonomy were considered disproportionate. The consequences of Independence were not only felt for the operational capacity of the prevention and control programmes, it had also made a change in people’s attitude towards rural hierarchies and social solidarity. Amongst others this was obvious from the attendance rates to the Sleeping Sickness mobile team surveys or to take part in bush clearing activities. The rates of attendance to the mobile teams’ visits fell from over 90% to levels as low as 30% and severe local resurgences occurred with prevalence’s rising from 0.01% to 12 or even 18%.

The costly large scale insecticide sprayings were gradually phased out everywhere. As an alternative the simple biconical trap was introduced in 1972, light weight, easy to handle and relatively cheap. These are appropriate for use by the communities themselves. In Busoga, Uganda during the seventies there was an outbreak as a result of the collapse of the cotton industry. The abandoned cotton fields, overgrown with lantana thicket, were infiltrated with tsetse flies and by 1980 the number of new patients exceeded 8500 per year. This epidemic was brought under control essentially by installing 10.000 tsetse traps, locally produced and looked after.

Many countries knew political upheavals involving refugees leaving their villages temporarily and often hiding in tsetse infested areas. Such villages were normally overgrown and infested with tsetse. It meant high exposure whilst hiding and again upon return. The recent outbreaks in Angola, the Democratic Republic of Congo, Southern Sudan and the adjacent West Nile district in Uganda are examples where the political situation led to severe outbreaks.

Smaller local outbreaks have been reported from practically all endemic countries. Such unpredictable flare ups, though costly to bring under control again, seem at the moment to be the unavoidable price to pay for scaling down preventive measures.