Characteristics of the Western Province, Zambia Trial Site for Evaluation of Attractive Targeted Sugar Baits for Malaria Vector Control

Background: The attractive targeted sugar bait (ATSB) is a novel malaria vector control tool designed to attract and kill mosquitos using a sugar-based bait laced with oral toxicant. Western Province, Zambia was one of three countries included in a phase III cluster randomized controlled trial of the Westham ATSB Sarabi version 1.2. The trial sites in Kenya, Mali, and Zambia were selected to represent a range of different ecologies and malaria transmission settings across sub-Saharan Africa. This case study describes the key characteristics of the ATSB Zambia trial site to allow for interpretation of the results relative to the Kenya and Mali sites. Approach This study site characterization incorporates data from the trial baseline epidemiological and mosquito sugar feeding surveys conducted in 2021, as well as relevant literature on the study area. Characterization of the trial site The trial site in Zambia was comprised of 70 trial-designed clusters in Kaoma, Nkeyema, and Luampa districts, spanning 175 kilometers with a population of 122,023. Population settlements in the trial site were dispersed and geographically vast villages with sparsely populated areas. The region was tropical with intense and seasonal malaria transmission. An abundance of trees and other plants in the trial site were potential sources of sugar meals for malaria vectors. Fourteen Anopheles spp. were endemic in the site and An. funestus was the dominant vector. Despite high coverage of indoor residual spraying (IRS) and insecticide treated nets (ITNs), the baseline malaria prevalence during the peak malaria transmission season was 50% among people ages six months and older. Conclusion Malaria transmission remains high in Western Province, Zambia despite coverage with vector control tools. New strategies are needed to address the drivers of malaria transmission in this region and other malaria endemic areas in sub-Saharan Africa.