GET a good night鈥檚 sleep: bed nets designed to stop mosquitoes in their tracks are undergoing large-scale trials in India and Tanzania.
Ordinary nets keep mosquitoes at bay, but the malaria-transmitting insects can still bite skin lying against the mesh. Coating nets with insecticide prevents this, but the chemicals tend to wash out of conventional yarns and so only offer effective protection for a few months.
Now the German firm BASF has developed a polymer mesh whose cross-linked structure can retain a pyrethroid insecticide inside it for 25 washes, yet still allows enough of the chemical to diffuse to the surface to 鈥渒nock down鈥� nearly all the mosquitoes that land on it.
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The amount used is not toxic to humans: the company says the net would be safe even if a baby were to suck it all night.
