Eradicating Flies to Improve Lives - IAEA Helps Countries in Africa to Combat Tsetse Fly

4 November 2013
The IAEA, through its Joint Division with the UN's Food and Agriculture Organization and its Technical Cooperation programme, supports 14 African countries in their efforts to combat the tsetse fly using the Sterile Insect Technique. One of these countries is Ethiopia. This photo essay focuses on the country's ongoing tsetse eradication project.Livestock are the lifeblood of African society and play a vital role in rural communities. According to the African Union's Interafrican Bureau for Animal Resources (AU-IBAR) an estimated 300 million people depend on livestock for their livelihoods.Animals are needed for ploughing land, transport and manure. They are used for food and meat and dairy products are sold at markets.Animals serve as a bank, for savings.  If a family needs funds for medical or school fees or a marriage, livestock are sold at market.Animal diseases pose a major threat. One such disease is nagana. According to the UN’s Food and Agriculture Organization it occurs in 37 countries in sub-Saharan Africa, costing an estimated $4.5 billion per year in lost agricultural production.Nagana is caused by the bites of tsetse flies. Many cattle, donkeys and goats die of the disease. The ones that survive have spontaneous abortions and their milk production suffers. The disease makes them too weak to be used for ploughing or transport.In Ethiopia, the government-run 'Southern Tsetse Eradication Project (STEP)' is aiming to eradicate the flies in a target area which covers 25 000 km<sup>2</sup> in the Southern Rift Valley.The project, with the support of the IAEA, is implementing the Sterile Insect Technique (SIT). With this method, millions of flies are reared. The male flies are sterilized using radiation.At the STEP facility in Addis Ababa, pupae are collected from the mass rearing room and stored. After 28 days the females are the first to emerge and the males emerge around 30 days after pupation.After all the females have emerged, the remaining male pupae are covered with a mixture of sand and fluorescent dye. This means they are marked as they leave their puparia and can be identified later as sterile males when trapped in the wild.The radiation damages the DNA in their sperm, making them infertile. When they are released into the wild they mate with females, but these produce no offspring.Before being packed for release, the flies are fed blood containing a drug that will prevent them from picking up the parasites that cause nagana.In April 2012, following area-wide suppression activities, the STEP project started aerial releases of sterile males over the Deme Basin region.Around 60 000 flies a week are being released. Eventually, when the sterile males outnumber their wild, fertile counterparts the population of tsetse flies will be eradicated.To monitor if the SIT is working, the STEP team based near the Deme Basin maintains traps in the area where the sterile males are being released.The team uses an  ultra violet light to identify the fluorescent dye put on the sterile males at the Kality facility in Addis Ababa to distinguish captured sterile flies from wild flies.Before the SIT can be applied, the flies need to be suppressed to very low levels using traps and insecticides. Such activities have been underway in the Arba Minch region since 2009.The STEP team here monitors the suppression by catching and counting flies, to check that their numbers are indeed decreasing.In this part of the Southern Rift Valley, the wild fly population is now down by over 90 per cent. The benefits of tsetse suppression can be seen all over the region.Not only are animals now for sale at markets, they are used for transport too. Dairy produce, such as milk and butter is widely available.Cattle are now available for ploughing land that several years ago was just forest. But fly suppression is not sufficient or sustainable in the long-term. The flies need to be eradicated.Once the area-wide tsetse suppression activities have advanced sufficiently and enough flies are being reared at the facility in Addis Ababa, the aerial releases of sterile males will begin here. <br /><br />© IAEA
Last update: 14 October 2014