Treated mosquito nets are safe and effective
For many decades Insecticide Treated Nets (ITNs) have been used to protect people against malaria. Due to their effectiveness, the use of ITNs has increased substantially across the African region. WHO recommends that all people at risk of malaria sleep under ITNs particularly long lasting insecticidal nets (LLINs) every night 
All Insecticide Treated Nets (ITNs) contain pyrethroids - the only group of insecticides recommended by the World Health Organization for use on mosquito nets. Pyrethroids are widely used in public health because of their safety for humans and ability to kill mosquitoes at low doses on contact.
Pyrethrins, an extract of the African flower Chrysanthemum cineriaefolium and synthetic Pyrethroids used in mosquito nets are very similar in their chemical structure and mode of action  .
Before insecticides are recommended by WHO, they undergo extensive laboratory testing to check if their use can cause acute and chronic toxicity. These tests help scientists judge how these chemicals might affect humans, domestic animals, and wildlife in the case of exposure.
Occasional side reactions that have been reported by bednet users include: headache, skin irritation, burning sensation in the eyes and nausea. However these effects, if they ever occur at all, are transient and mild. Studies have revealed neither asthma nor cancer in infants and young children as a result of the use of bednets 
Pyrethroids do not pose any significant health risk when they are used in mosquito nets and in-door house spraying. It is recommended that Member States continue to procure and scale up the use of WHO-approved LLLNs  for universal access. This will further consolidate the significant gains already made through their use in malaria control.