Greater incentive to sting
Mosquitoes love this trick: how viruses change people’s body odor to make it more attractive to mosquitoes
Some viruses can ensure that human body odor turns into a lure for mosquitoes. As a result, mosquitoes bite more often, thus accelerating the spread of the virus itself.
It is an alliance that no one needs. When viruses and mosquitoes cooperate, it rarely bodes well. Mosquitoes play an important role as vectors of various infectious agents. But not only that: a research group from Tsinghua University in Beijing is now reporting that some viruses, to put it bluntly, can do a kind of magic trick. They ensure that mosquitoes can smell infected people particularly well. The result: points. Many, many points.
As the research team in the journal Cell reports, people infected with the Zika or dengue virus secrete a substance that races particularly like. Bacteria are responsible for development, which can multiply particularly well on the skin due to so-called flavivirus infection. The substance, acetophenone, acts as an attractor for mosquitoes.
Mosquitoes are attracted to the smell
Scientists noticed this mechanism when they worked with mice. They observed that mosquitoes bite mice infected with dengue or Zika virus and then examined the odor molecules of healthy and infected mice. As a result, they identified the acetophenone molecule. In healthy people, an antimicrobial protein prevents this odorant from developing excessively. However, if a person is infected with flavivirus, this protein (RELMA) is suppressed and cannot “work” as usual. Researchers assume that the virus manipulates the microbiome of the infected so it can spread better.
The key to countering the mechanism can be found in acne remedies. Among other things, isotretinoin is used in these. This increases the production of RELMα. Mice fed the vitamin A derivative were no more bothered by mosquitoes than healthy mice. So they were bitten less often. However, isotretinoin does not work against the viral infection itself.
The research team also sees the discovery as an opportunity for infection prevention. In the future, scientists also want to treat human dengue patients with isotretinoin preparations. They hope, according to Gong Cheng, who is part of the research team, that this “reduces the activity of mosquitoes” caused by acetophenone. This could then curb the spread of dengue fever.