A mosquito net offers protection against mosquitos, flies, and other insects, and thus against diseases such as malaria. Its fine, see-through, mesh construction stops many insects from biting and disturbing the person using the net. The mesh is fine enough to exclude these insects, but it does not completely impede the flow of air.

Mosquito nets are often used where malaria or other insect-borne diseases are common, especially as a tent-like covering over a bed. For effectiveness, it is important that the netting not have holes or gaps large enough to allow insects to enter. Because insects can bite through the net, the net must not rest directly on the skin.

Mosquito nets treated with insecticides -- known as insecticide treated nets (ITNs) -- were developed in the 1980s for malaria prevention. These nets, impregnated with a pyrethroid insecticide like deltamethrin or permethrin, kill and repel mosquitoes. Unfortunately, standard ITNs must be replaced or re-treated with insecticide after six washes and, therefore, are not seen as a convenient, effective long-term solution to the malaria problem.

As a result, the mosquito netting and pesticide industries teamed up to develop so-called long-lasting insecticidal mosquito nets (LLINs), which also use pyrethroid insecticides, but are also treated with a chemical binder that allows the nets to be washed at least 20 times, allowing use for three or more years.