WHO recommend coverage for all at-risk persons; and in most settings. The most cost effective way to achieve this is through provision of free LLINs
so that everyone sleeps under a LLIN every night. Indoor spraying with residual insecticides: indoor residual spraying (IRS) with insecticides is a powerful way to rapidly reduce malaria transmission. Its full potential is realized when at least 80% of houses in targeted areas are sprayed.