WP4 aims to determine the efficacy of AL+AP in preventing human-to-mosquito transmission of P. falciparum and preventing the development of mosquito stage of P. falciparum (Study IV). The first part of its activities (blocking transmission from human-to-mosquitoes) will be realized at the clinical site level in Benin, Gabon, Ghana, and Mali. WP4 is responsible for the training of local entomologists on membrane feeding assays and will monitor the implementation of the assays locally. This includes the development of SOPs. WP4 will supervise the upgrade of local insectarium in Ghana, Mali, Gabon and Benin to level 2. The second part of the Study IV will be done in Bobo Dioulasso, Burkina Faso by IRSS. As an exploratory study it will measure the effect of serum from patients treated with AL+AP, and administered in second blood meals to P. falciparum-infected mosquitoes, on ookinete/oocyst infection. The WP4 research activities are nested into the WP2, as it requires sampling from the clinical trial patients. WP4 will interact with WP5 for the data management and analysis.