Tsetse flies have plagued sub-Saharan Africa for ages. The winged insect’s bite can kill both animals and humans as well. Now researchers in Kenya seem to have found a remedy.
One of East Africa's tourist highlights is seeing Massai ethnic nomads in their traditional red attires, leading herds of cattle in search of pasture. Cows are an important aspect for the Maasai community. They are not only a source of food but they also provide income for the family.
Drought as well as lack of water and grazing land have always been major challenges for Massai herders, but another enemy made this mix deadlier: The tsetse fly.
According to Nguya Maniania, a Congolese scientist who works at the International Centre of Insect Physiology and Ecology (ICIPE) in Kenya's capital Nairobi, insects also carry bacteria, fungi and viruses, just as humans do. "The good news is that not all the germs the insects carry are dangerous to humans," Maniania said. Still, he regards tsetse flies as a formidable opponent.
A bite that increases the plight
Tsetse flies can transmit a deadly disease known as Nagana. Three million heads of cattle die annually in Africa as a result of this infection. Nagana kills the animals not only faster, but makes them produce fewer calves and milk beforehand. Consequently cattle owners yield less meat from affected animals.
Kenya had previously conducted numerous campaigns to exterminate tsetse flies, but with little success. Since using chemicals on a large scale to fight the insects is out of the question, Nagana continued to reduce the number of animals and thereby contributed to a rise in poverty rates.
Now a solution appears within reach. Scientists from ICIPE have discovered a tsetse fly repellent taken from waterbucks. "We identified this chemical because we know that tsetse flyies do not feed on waterbucks," says Rajinder Kumar Saini, head of the Animal Health Division and Principal scientist at ICIPE.
The waterbuck compound is put in a dispenser that forms part of a collar worn by cattle. The repellent doesn't have to be placed only around an animal's neck. Saini says that it can be placed anywhere in the farm.
The simple device has reduced tsetse bites by as much as 90 percent.
Noticed beyond Kenyan borders
Farmers have noticed a difference between protected and unprotected herds, Saini says. "The waterbuck compound is not very expensive. One can buy it from the market and mix it in the ratio needed," he adds.
The European Union, which largely funded the project, requested ICIPE to find commercial partners, who could take up production of the repellent. The Kenya Research Development Institute has so far taken up production. A Swiss company has agreed to expand and evaluate the possibility of using such compounds for other flies worldwide.
Author: Asumpta Lattus / cm
Editor: Daniel Pelz / rm