Indoor Residual Spraying (IRS)

Photo of a man spraying insecticide on a wall

Indoor residual spraying (IRS), a proven and highly effective malaria control measure, involves the spraying of residual insecticide on the interior walls of homes to kill mosquitoes, thereby interrupting malaria transmission. IRS confers community protection when at least 80 percent of houses in a targeted area are sprayed. There are only four insecticide classes [PDF, 16KB] approved by the World Health Organization Pesticide Evaluation Scheme (WHOPES). When insecticide resistance to one class is detected, rotating to another class can mitigate resistance in vector populations, which is currently one of the greatest challenges to malaria prevention programs.

PMI-supported IRS activities include assessing the environment to ensure safe and effective use of insecticides, educating residents about the benefits of IRS, training spray teams, procuring insecticide and equipment and developing and evaluating spraying activities. Furthermore, PMI has been a global leader in building the capacity of countries to conduct comprehensive entomological testing, including insecticide resistance monitoring. This has provided robust data to PMI-supported IRS programs, enabling better decision-making about where and with which insecticides to spray. PMI undertakes research and conducts analyses to track trends, for example, on insecticide resistance and costing (see Partner Reports tab).

Safeguarding the Environment

Promoting the safe and judicious use of pesticides is a core component of PMI. As a federal agency, the U.S. Agency for International Development (USAID) is subject to U.S. environmental regulations, which ensure that development programs are not only economically sustainable, but also protect the host country’s residents, malaria control workers and environment. USAID’s environmental regulations are defined in 22 CFR 216 and are consistent with global environmental standards for use of insecticides in public health programs.

To support overarching PMI issues, USAID engaged in a Programmatic Environmental Assessment (PEA) for insecticide-treated materials and integrated vector management, including IRS. The PEA is used to guide the follow-up country-specific Supplemental Environmental Assessments, which include “safer use action plans” in any country where support includes the use of pesticides. USAID and PMI policies and procedures for improving the safe and judicious use of pesticides are closely aligned with international standards and regulations, which can be found in the Guidance tab.

Programmatic Environmental Assessments

To support overarching PMI issues, USAID engages in a Programmatic Environmental Assessment (PEA) for insecticide-treated materials and integrated vector management, including indoor residual spraying. USAID and PMI policies and procedures for improving the safe and judicious use of pesticides are closely aligned with international standards and regulations.

Country-Specific Supplemental Environmental Assessments

The PEA is used to guide the follow-up country-specific Supplemental Environmental Assessments., which include "safer use action plans" in any country where support includes the use of pesticides.

Liberia

Madagascar

Malawi

Mali

Mozambique

Rwanda

Uganda

Zambia

Photo source: RTI International