section_path: Prevention/Mosquito control/Insecticide-treated nets
section_name: Insecticide-treated nets
paragraph_text: Insecticide-treated nets
  
  Mosquito nets help keep mosquitoes away from people and reduce infection rates and transmission of malaria. Nets are not a perfect barrier and are often treated with an insecticide designed to kill the mosquito before it has time to find a way past the net. Insecticide-treated nets (ITNs) are estimated to be twice as effective as untreated nets and offer greater than 70% protection compared with no net. Between 2000 and 2008, the use of ITNs saved the lives of an estimated 250,000 infants in Sub-Saharan Africa. According to UNICEF, only 36% of households had sufficient ITNs for all household members in 2019. In 2000, 1.7 million (1.8%) African children living in areas of the world where malaria is common were protected by an ITN. That number increased to 20.3 million (18.5%) African children using ITNs in 2007, leaving 89.6 million children unprotected and to 68% African children using mosquito nets in 2015. The percentage of children sleeping under ITNs in sub-Saharan Africa increased from less than 40% in 2011 to over 50% in 2021. Most nets are impregnated with pyrethroids, a class of insecticides with low toxicity. They are most effective when used from dusk to dawn. It is recommended to hang a large "bed net" above the center of a bed and either tuck the edges under the mattress or make sure it is large enough such that it touches the ground. ITNs are beneficial towards pregnancy outcomes in malaria-endemic regions in Africa but more data is needed in Asia and Latin America.
  
  In areas of high malaria resistance, piperonyl butoxide (PBO) combined with pyrethroids in mosquito netting is effective in reducing malaria infection rates. Questions remain concerning the durability of PBO on nets as the impact on mosquito mortality was not sustained after twenty washes in experimental trials.
  
  UNICEF notes that the use of insecticide-treated nets has been increased since 2000 through accelerated production, procurement and delivery, stating that "over 2.5 billion ITNs have been distributed globally since 2004, with 87% (2.2 billion) distributed in sub-Saharan Africa. In 2021, manufacturers delivered about 220 million ITNs to malaria endemic countries, a decrease of 9 million ITNs compared with 2020 and 33 million less than were delivered in 2019". As of 2021, 66% of households in sub-Saharan Africa had ITNs, with figures "ranging from 31 per cent in Angola in 2016 to approximately 97 per cent in Guinea-Bissau in 2019". Slightly more than half of the households with an ITN had enough of them to protect all members of the household, however.