Itching mosquito bites Some people are stung much more often

Some people are stung more often by mosquitoes
One wakes up with countless mosquito bites, the other does not have a stitch. In the vernacular is therefore the motto: "mosquitoes sting especially those who have sweet blood". But what is the myth? This question has been answered by James Logan of the London School of Hygiene and Tropical Medicine as part of a study with his team.

Not by the "sweet blood", but by the body odor of humans mosquitoes are really attracted, the scientists report. This realization is not new. Unknown until now was the fact that some people are more stung by mosquitoes than others. Using a set of experiments with pairs of twins, the researchers studied the behavior of mosquitoes. The study involved 18 identical male and 19 dizygotic, mostly female, twin pairs. Twins have largely genetically identical structures. The subjects had an age range between 50 and 90 years.

Mosquitoes love the dusk and certain blood? (Image: mycteria / fotolia.com)

Y-containers fly the mosquitoes directly onto the hands
The participants had to expose themselves to the attacks of the mosquitoes. For this, the Stechtiere were channeled through a special flight channel, which split after only a short distance like a "Y" in two ways. The mosquitoes then arrived at the hands of the participants. At the end of the flight channel, the mosquitoes could decide which hand they prefer to sting. The smell was crucial here. For the experiment only female yellow fever mosquitoes (Aedes aegypti) were used, which were between 5 and 7 days old. 20 small mosquitoes always flew through the tube. The Y-shaped tube was simultaneously an odor analyzer (olfactometer).

Prior to the experiment, subjects were advised not to consume alcohol or other strong-smelling foods, such as garlic, cabbage or chilli.

Genetic differences caused more mosquito bites
The result showed that there were almost no differences in the identical twins. The siblings were about equally popular or unpopular with the mosquitoes. For the dizygotic twins, who have genetic differences, the results were completely different. "One of the two was much more popular than the other," the scientists write in the study report. In another work, the genetic peculiarities are now to be found.

New approach in the fight against malaria and dengue fever
For the scientists, however, do not want to design a new mosquito repellent commercially, but find a way to protect people in the future from the transmission of dangerous infectious diseases such as malaria or dengue fever. "Every year over one million people die as a result of transmitted diseases," says James Logan. "Understanding the genetic basis for variation between individuals may allow us to develop tailor-made means to better control mosquitoes and new defenses," he said. This approach could lead to "better protection against diseases transmitted by biting insects". Home remedies for mosquitoes such as garlic or beer are said to sting the mosquitoes, according to the study. (Sb)