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New drug against sleeping sickness: "Antelope Perfume" repels Tsetse flies


Keep Tsetse flies away from cattle with "antelope perfume"

The sleeping sickness, which is widespread in large parts of Africa, can also lead to death if left untreated. Not only in humans, but also in cattle. The infection is transmitted by Tsetse flies. Researchers have now found a way to keep insects away from cows: using an “antelope perfume”.

Sleeping sickness can lead to death

Sleeping sickness (African trypanosomiasis) is, according to “Doctors Without Borders”, one of the most neglected diseases in which research is under-invested. It is transmitted by the tsetse fly and ends fatally without treatment. "In the final stages, the parasites damage the central nervous system, which leads to sleep disorders, reversal of the sleep-wake rhythm, changes in behavior, mental confusion and ultimately death," the experts write on their website. Tropical disease also poses a massive threat to animals. An international team of scientists has now researched how the disease can be prevented.

Broadcast by widespread flies

Tsetse flies are common in Africa. They feed on blood and can transmit the dreaded sleeping sickness.

The first symptoms include severe headache, insomnia, swollen lymph nodes, anemia and a rash.

In the late stages of the disease there is progressive weight loss and a twilight state that has given the disease its name. If the infection is left untreated, it will be fatal.

Numerous people in tropical Africa are directly at risk, but the transmission to cattle also has drastic consequences for agriculture: cattle, milk, meat and labor have declined.

The damage in Africa is estimated to be around $ 4.6 billion a year.

Tsetse flies don't like the smell of antelope

Prof. Dr. Christian Borgemeister from the Center for Development Research (ZEF) at the University of Bonn now has a team of researchers from the International Center of Insect Physiology and Ecology (icipe), the Interafrican Bureau for Animal Resources (both in Kenya) and Rothamsted Research, Harpenden (Great Britain ) takes a new approach in the fight against sleeping sickness.

The Tsetse flies avoid waterbucks, an African antelope species, because they find the smell of the animals repugnant.

According to a message from the University of Bonn, the international team of scientists first isolated, identified and synthesized the waterbuck's antibodies.

The researchers filled tiny amounts of the Tsetse fly-repellent substance into plastic containers that were tied to the cattle with a collar.

From then on, the cattle gave off the smell of the unpopular waterbuck - like the famous wolf in sheep's clothing, the Tsetse flies were deceived by the "antelope perfume".

Waterbuck smell reduces disease rates by more than 80 percent

The innovative disease prevention method was tested in a large two-year field trial in Kenya. 120 Maasai herders provided more than 1,100 of their cattle for the experiment.

As the researchers report in the journal "PLOS Neglected Tropical Diseases", the disease rates of the animals treated with the repellent were reduced by more than 80 percent compared to unprotected cattle.

In general, the animals with the protective collar were healthier, heavier, gave more milk, were able to plow more land and achieved significantly higher sales in the regional markets.

Particularly attractive and promising approach

"All of this contributed to a significant improvement in the food security and household income of the shepherd families involved," explained Borgemeister.

In comparison to the other veterinary medicines used, the collar method is significantly cheaper and therefore more economical, according to the researchers.

In addition, the new technology was very well received by the Maasai herders. Around 99 percent of shepherds would like to use the collars.

"This method, which has been successfully tested in practice, represents a major advance in the food security of many shepherds and livestock farmers in Africa," said Borgemeister.

Since the collars with the repellent are easy to use and do not cause high costs, this procedure is particularly attractive and promising. (ad)

Author and source information


Video: Filipa Rijo-Ferreira UTSW: Circadian Rhythms of the African Sleeping Sickness Parasite (October 2021).