Malaria-immune human sera were tested for their ability to affect the infectivity of Plasmodium falciparum gametocytes to Anopheles stephensi mosquitoes. Transmission-reducing effects of the sera were associated with the presence of antibodies to the gamete surface protein, Pfs230. Enhancement of transmission, manifest as elevated numbers of oocysts relative to controls, was observed for a number of sera, but was not found to be associated with antibodies against Pfs230. These results confirm that Pfs230 is a possible candidate for inclusion in a transmission-blocking malaria vaccine.
