Some viruses make people more attractive to mosquitoes, study shows
When a mosquito bites and infects you with a virus like dengue or Zika, it also makes you smell good to other mosquitoes, new research suggests.
That makes it more likely another one will bite, pick up the virus and carry it to the next victim.
“The virus can manipulate the hosts’ skin microbiome to attract more mosquitoes to spread faster,” said study coauthor Penghua Wang, an immunologist at UConn Health in Farmington, Connecticut.
The findings could explain how mosquitoborne viruses persist for such a long time, researchers said.
Both dengue and Zika are spread by mosquitoes.
Dengue affects 50 million people a year and kills 20,000, mostly children, according to the National Institute of Allergy and Infectious Diseases.
Zika can cause serious birth defects in the unborn children of infected pregnant women, though it rarely causes serious problems in adults.
To keep spreading, both viruses require ongoing infections in hosts. If all mosquitoes died or all susceptible hosts cleared the virus, the viruses would disappear.
But there are always mosquitoes in tropical climates, and the viruses just need one to bite a host to be able to spread.
Researchers suspected the viruses might be altering people’s scent in some way to attract mosquitoes.
They found that mosquitoes seemed to prefer mice infected with dengue more than healthy mice.
They tested several molecules that were more common on infected animals. They applied these to mice and humans.
One molecule, acetophenone, was especially attractive to mosquitoes.
Similarly, skin odorants from people with dengue found more acetophenone and that these patients also were more attractive to mosquitoes.
Researchers also tested a potential preventative
— a vitamin A derivative called isotretinoin that increases production of the skin’s protective antimicrobial peptide. Mice treated with isotretinoin were less attractive to mosquitoes.
The next step is to analyze more human patients with dengue and Zika, Wang said.
The findings were published in the journal Cell.