By Zablon Oyugi
The Food and Agriculture Organization of the United Nations (FAO) has released first-ever Africa-wide tsetse flies distribution map to help in combating the trypanosomiasis disease, also called nagana, in cattle in the continent. The lethal parasitic disease causes billions of dollars in economic losses for livestock farmers in subSaharan Africa.
The disease, which is caused by the blood-sucking tsetse fly, hinders milk and meat production, as well as the animals’ ability to work. This has led to food insecurity and decreased income for millions of African farmers who depend on livestock. Tsetse flies act as incubators and carriers for trypanosomes, single-celled parasites that cause the debilitating and often fatal disease. In humans, this disease is also known as sleeping sickness, as it affects the nervous system and manifests symptoms such as fatigue, severe headaches, and coma.
If not diagnosed and appropriately treated, the disease almost invariably leads to death. While sleeping sickness is no longer considered a public health problem, with fewer than 2,000 cases reported each year in humans, the disease still severely affects livestock in Africa.
Efforts to control and eliminate animal trypanosomiasis require decisions based on sound evidence. However, the last continental maps of tsetse distribution in Africa were developed more than half a century ago, and no Africa-wide map of animal trypanosomosis occurrence has even been generated.
The FAO atlas is the first significant step in filling such data gaps. Its data on tsetse distribution is based on 669 scientific papers spanning 31 years (from 1990 to 2020). It combines geolocation data such as Google Earth with entomological fieldwork, including stationary traps and fly rounds using mobile devices.
Tsetse fly distribution
In total, 7,386 sites across Africa were analysed, producing the most comprehensive maps to date of the tsetse fly’s distribution on the continent.
This kind of data will be vital for practitioners on the ground and policymakers in the affected countries, as well as for scientific researchers and international organisations such as the World Health Organization (WHO), with which FAO is working closely in the fight against sleeping sickness. The atlas also provides a blueprint for the development of national information systems.
With FAO’s support, veterinary authorities in Burkina Faso, Ethiopia, Ghana, Kenya, Mali, Sudan and Zimbabwe have already adopted FAO’s methodological approach.
“We are hopeful that these tools will help reinvigorate initiatives aimed at removing this major hurdle to sustainable development in Africa and thus contribute to the vision of a healthy world, free of poverty and hunger,” Thanawat Tiensin, the Director of FAO’s Animal Production and Health Division, wrote in the atlas’ forward.
Next steps
The atlas was developed by FAO within the framework of the Programme Against African Trypanosomiasis (PAAT), with financial support from FAO, the government of Italy, the European Union and WHO. Updates to the atlas are planned, along with a new publication to fill the second significant data gap: continental maps of animal trypanosomiasis.