A trio of instruments for tsetse control

Africa may be the birthplace of humanity but for hundreds of thousands of years, human activity on the continent has been constrained by unpredictable climates, harsh environments, pests and more disease-causing parasites than exist anywhere else in the world. Whilst the hundreds of migrants that were the first to leave Africa dispersed, thrived and multiplied, those that remained behind continued to struggle to survive. Over the millennia many parasites, including malaria and bilharzia, have affected people's potential to prosper but one insect pest - the tsetse (Glossina Spp.) - and the parasite it carries has, above all, limited the land available for cultivation and the spread of domesticated livestock. Despite many and various approaches to its control over the past 100 years, tsetse remains unchanged and the affect of the trypanosome species that it transmits continues to affect millions of poor people and their livestock. The challenge today, according to Ian Maudlin, Programme Manager for the DFID Animal Health Programme, is to provide tools for the individual farmer so he can deal with the problem of tsetse and trypanosomiasis in his own way and in his own time.

During the past year there has been some healing of the divisions (see Points of View: A testing time for tsetse eradication ) within the international tsetse and trypanosomiasis community on the best way forward for tsetse control, and it is clear that future disease management strategies should encompass a broad range of control options for use in different circumstances. One tool will not fit all. With this in mind, recent advances in several livestock keeper-based tsetse control strategies were discussed at a workshop held in Nairobi in October 2003 with the aim of taking new knowledge in each area to a point where promotion and application of each of three technologies could be realised.

1) Restricted application: a reason for restraint?
One of the best-known techniques of farmer-based control of tsetse is the application of insecticides - pyrethroids - to cattle...

2) A net advantage for zero-grazing
Small-scale farmers produce the majority of Kenya's milk but, many of the cows are kept in zero-grazing pens where they are a sitting target for biting flies, including tsetse...

3) A harmonious approach
What is it about a warthog that makes it so attractive to tsetse and yet waterbuck and zebra remain free of the effects of tsetse and the trypanosomes they carry?

From a researcher's point of view each of the three technologies will continue to be tested and refined. But for farmers anxious to protect their cattle any one of these approaches, all of which have proved to be effective and simple to use, could be used without further discussion. However, the difficulty of technology transfer in Africa is not only whether these tools are commercially viable but that Africa's range of climates, habitats, pests and diseases means that each technology will have to prove itself against the continent's diversity if they are to be truly successful against tsetse.