Abstract: The inventors have identified Pfs47, a gene from the malaria parasite P. falciparum, as a key factor for survival of these parasites in the mosquito Anopheles gambiae. A. gambiae is a major natural vector of human malaria in Africa. The Pfs47 protein may allow the parasite to survive in the mosquito by manipulating the mosquito's immune system. The inventors propose the use of P47 proteins, including Pfs47 and Pvs47 as a target of vaccines or pharmaceutical agents that will block or reduce P. falciparum or P. vivax infection in A. gambiae or other anopheline mosquitoes and thus prevent further transmission of the parasites in humans.