Mosquitoes that carry malaria mainly bite in the evening and early night so it is important to reduce the chances of being bitten during this period. Studies have shown that using insecticide-treated nets in sub-Saharan Africa reduces both malaria illness and the number of deaths in children under five. Use of insecticide-treated nets by pregnant women also reduces anaemia among mothers, the number of low birth weight babies and the number of babies that die before delivery.
Long-lasting insecticide-treated nets are most effective where transmission intensity is moderate-to-high and when everyone sleeps under a treated net every night. It is estimated that, in areas where malaria is common, the use of insecticide-treated nets can save the lives of an average of 5.5 children for every 1,000 children protected.
To achieve this level of protection, it is important that programmes distributing and promoting the use of insecticide-treated nets are effective. Ideally, distribution programmes need to ensure that a high proportion of the population is covered and long-lasting insecticides are used.
You can find more information on insecticide-treated nets in:
Cochrane Database of Systematic Reviews - Insecticide-treated bed nets and curtains for preventing malaria