AFRICA: Can sterile tsetse flies save African agriculture?

AFRICA: Can sterile tsetse flies save African agriculture?

DAKAR, 12 May 2009 (IRIN) - Each year in Africa the tsetse fly causes more than US$4 billion in agriculture income losses, kills three million livestock and infects up to 75,000 people with trypanosomiasis, according to the UN. Though sterilising the flies may help wipe out the offending parasite, it is a long, expensive process that is losing experts to other more well-funded health research, according to scientists.

 The head of the human African trypanosomiasis ("sleeping sickness") programme at the Geneva-based Foundation for Innovative New Diagnostics (FIND), Joseph Ndung'u, told IRIN he left his position as director of the Kenyan Trypanosomiasis Research Institute in order to expand his work beyond Kenya.

 "But it is true that many scientists [in Africa] are moving away from tsetse flies to other diseases that are seen as more sexy," he said.

 Ndung'u said the steep drop in the number of humans affected by trypanosomiasis - from an estimated half-million a decade ago to 75,000 in 2007 according to World Health Organization (WHO) - has reduced funding for tsetse fly research, surveillance and disease control.

 "But the disease is still as deadly in animals," Ndung'u added. The parasite causes "wasting disease", or nagana, which leads to fever, anemia and possibly death.

 Without these animals, sub-Saharan Africans earn, eat and produce only a fraction of what they could otherwise, according to the UN Food and Agriculture Organization (FAO).

 Poverty fly

 "It is a poverty fly," said Jorge Hendrichs, the head of the insect and pest control section of a joint FAO and International Atomic Energy Agency (IAEA) project. "Why are there lush green areas with very hungry poor people? Look closer and you will notice women working the land with their bare hands. There are simply no animals in the poorest rural areas of Africa. Tsetse [flies] have killed the cattle that would have pulled plows in the fields or transported food to the market."

 Ninety percent of the crops grown in sub-Saharan Africa are produced without animal power, which costs the continent more than $4 billion in losses every year, according to FAO.

 Nuclear

 By sterilising male flies with radiation and releasing them into endemic areas, scientists have been able to wipe out a number of species over the past 50 years.

 But IAEA's Hendrichs told IRIN despite that this technique was effective for the Mediterranean fruit fly in Mexico and the melon fly in Japan, only Tanzania has declared itself tsetse fly free after donors helped fund a $6-million sterilisation project in the late 1980s.

 The most heavily affected countries include Uganda, the Democratic Republic of Congo  and Angola.

 IAEA director Hendrichs told IRIN a lack of experts and poor management have held back tsetse fly elimination in Africa. "Tsetse flies are partly an insect problem, but it is also a human resource management issue. These programmes are not simple. You need a lot of political will. You cannot run it through any government bureaucracy. You need to create reliable management teams that are not corrupt or [do not] have other interests."

 Hendrichs added that qualified scientists and IAEA-trained civil servants tend to leave Africa to seek higher-paying employment elsewhere. "A number of the [IAEA] fellows disappear into the private sector, or simply disappear during training."

 IAEA trains up to 20 scientists every year on tsetse fly control.

 FIND scientist Ndung'u told IRIN he is sticking with tsetse flies. "Whereas the impact [of our work] on humans may not be so obvious, the link to Africa's agriculture is what makes tsetse flies so important. With oxen to pull plows, you can produce 10 times more, feed yourself and your children and have enough to sell at the market."

 He added: "If we want to make a difference in Africa, our work must start and end with tsetse flies."