A primary means of increasing agricultural productivity to reduce global food insecurity is through intensification, including scaling irrigation measures (USAID, 2014). Aid agencies have strongly promoted agricultural intensification efforts to increase productivity and improve overall livelihoods. While scaling of irrigated agriculture has demonstrated significant boosts in productivity (ADB, 2013; Melaine & Nonvide, 2017), agrarian transformation of the landscape through irrigated agricultural practices is associated with a number of water-related diseases (Hunter et al., 1993; Lacey & Lacey, 1990; Mather & That, 1984) including malaria (Ghebreyesus et al., 1999; Koudou et al., 2005; Oomen, De Wolf, & Jobin, 1988). The government of Malawi established through the Green Belt Initiative (GBI) a long-term program aimed at land use modifications for the development of small and large-scale irrigation. While Malawians continue to face challenges directly related to food insecurity, the country is simultaneously holoendemic for malaria, wherein the disease is found in essentially all members of the population.This research investigates changes in disease dynamics of seasonal malaria cycles as a result of land transformation for irrigated agriculture using remote sensing and spatial analytical approaches. It is conducted against a backdrop of scaling up irrigated agricultural solutions across varying sectors, and myriad actors. To that end, the meaning of 'scaling up' is analyzed across Research and Development (R&D;) institutions and a conceptual framework of scaling up was constructed to promote ontological agreement of scaling up from defining programs through to final evaluation of success. Three scenarios for estimated spatio-temporal distribution of suitablearea for mosquito breeding pool formation and persistence were produced for the Bwanje Valley Irrigation Scheme (BVIS) using remotely sensed and field-based data. In addition, an estimation of habitat suitability during the dry season was produced for the 8-km area surrounding BVIS, the Bwanje Valley. Potential malaria transmission at the national scale driven by the GBI is presented through analysis of the current extent of irrigated agriculture, proposed expansion, and historic malaria prevalence data assessed by the 2012, 2014, and 2017 Demographic Health Survey (DHS) in combination with the results of a habitat suitability model generated in Google Earth Engine. The conclusions from this study provide a strong foundation for agricultural land use decision making with respect to malaria transmission across Malawi.
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