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Protection against malaria: The smell of sweat is said to turn cows into mosquito baits


Mosquitos that transmit malaria attract the smell of human perspiration. That's why scientists in California developed a vaccine that makes cows smell like human sweat to attract mosquitoes to cows.

Bad air?
The ancient Romans called malaria, bad air, the life-threatening fever, whose pathogens transmit mosquitoes when they suck blood. Since the Romans knew nothing about viruses and bacteria, but saw that people near the swamps contracted the fever, they considered the air there to be the cause.

Mosquito larvae hatch in the water
Mosquito larvae develop in stagnant water, which explains why malaria is rampant around swamps. Where there is no water, there are no mosquitoes that could transmit malaria.

No tropical disease
Malaria is not a tropical disease, but historically spread not only in Italy, but also in Germany. Today it mainly affects people in the wetlands of Africa, America and Asia. The most dangerous variant is used in Africa, “tropical malaria”.

Avoid malarian
The best protection against malaria is to avoid mosquito bites. So far, mosquito nets or mosquito sprays have been used for this. But in 2015, 212 million people still contracted the disease and every second infected person died of it.

Africa in the center
The disease is worst in sub-Saharan Africa. Here the scientists are now trying their sweat scent on cows and goats.

Stab and die
Isca technologies developed the substance that smells like human swear and that African farm animals now receive. A deworming agent is also included. As a result, the mosquito dies immediately after the bite, after the scent previously lured it onto the beef or goat.

Animal cruelty?
The animals do not fall ill, so the sting is without consequences for them.

Tests in Tanzania
Tanzania is particularly affected by malaria (Malaria tropica), there is a year-round risk of less than 1800 m across the country. Goats and cattle are also the most important farm animals in large parts of the country. Here the biotech company tested the vaccine. The first results promise success: the number of cows stung increased significantly; the number of people stabbed decreased significantly.

No one hundred percent protection
The new agent will not guarantee 100% protection against malaria either. But especially for people in the Third World, it can reduce the risk of getting infected.

Chemoprophylaxis
The following malaria prophylaxis drugs are currently available: chloroquine, proguanil, mefloquine, atovaquone, artemether, doxycycline, sulfadoxine pyrimethamine.

Repellents
Insect repellents, on the other hand, help to be stung in the first place. The most effective remedy on the skin is DEET. Icaridin preparations are also very suitable. Mosquito nets can be impregnated with cyfluthrin.

Solid clothes
Fleece fabrics or wool sweaters provide good protection against mosquito bites, but are hardly wearable in tropical heat. In outdoor shops, on the other hand, there are long-sleeved shirts and trousers that are adapted to the heat and are still mosquito-proof.

Inexpensive alternative?
But the current drugs for malaria are so expensive that the local people can usually not afford them. In addition, they are usually not available. Many locals don't even have long-sleeved shirts and trousers, as well as shoes that cover their ankles. (Dr. Utz Anhalt)

Author and source information


Video: Peter Doherty: Disease in a Borderless World (June 2021).