Mosquitoes are responsible for about 350 million human illnesses each year, a number that will surely increase as climate change increases the number of disease-carrying insects. A recent study even shows how another human impact, light pollution, may be responsible for extending the blood draw season in mosquitoes.
New research into bite protection has taken a readily available natural molecule, cellulose, and manipulated it to produce a product that reduces mosquito bites on human skin by 80%.
Found abundantly and cheaply in industrial waste inputs, local food, and paper waste, cellulose aggregates into nanocrystals when treated with sulfuric acid. These cellulose nanocrystals (CNC) form a strong, transparent barrier film.
The scientists found that, mixed with water and a small amount of glycerol, these CNCs could be applied to the skin as a spray or gel and block the mosquito’s ability to bite through the skin to draw blood.
Female mosquitoes need human or animal blood to produce eggs, so a significant reduction in this food source, especially in densely populated areas, could have a positive impact on controlling mosquito populations.
CNC and efficient barrier forming have been developed for a wide range of “green” uses, including soundproofing, removing ink from fabrics, and making strong binders such as superglue and composites as strong as bone.
In trials with mosquitoes in Egyptian temples Lead researcher Daniel Voignac, of the Robert H. Smith School of Agriculture, Food and Environment at the Hebrew University of Jerusalem, and his colleagues tested CNC-treated and untreated hands, exposing the skin for 10 minutes inside a mosquito cage which is closed with an average of 15 females.
The result was that the thin film of CNC gel acts as a chemical camouflage, with an 80% reduction in bites compared to a hand exposed to the insects without the biomaterial barrier.
Other studies have shown that the CNC coating also blocks the passage of ammonium hydroxide vapor, a common mosquito attractant when applied to filter paper and exposed to insects.
Species are everywhere Ah. in Egypt y Ah. White hair is vectors of more than 22 serious arboviruses, including dengue, chikungunya, Zika, Japanese encephalitis, Rift Valley fever, yellow fever, and West Nile virus.
Although at a preliminary stage, the research shows promise for the development of cheap and transparent natural compounds that could block the release of skin chemicals that alert female mosquitoes to a blood feast.