Introduction to indoor residual spraying (IRS)

Environmental management and other larva killing activities are important in malaria prevention. Larval control is the first line of defense in malaria prevention; its impact in reducing the burden of malaria can be significant in those developing countries where vector breeding sites are relatively limited and generally clearly defined. However, it is impossible to identify all vector breeding sites and kill all larvae before they become flying adults. Once mosquitoes become flying adults, environmental management has little impact in controlling them, so measures to control adult mosquitoes are needed to protect people from malaria.

Indoor residual spraying (IRS) has three main aims:

1. To reduce the seasonal rise in malaria.
2. To prevent epidemics.
3. To control epidemics.