A genetically engineered parasite vaccine provides protection from controlled human malaria infection.

Genetically engineered live sporozoites constitute a potential platform for creating consistently attenuated, genetically defined, whole-parasite vaccines against malaria through targeted gene deletions. Such genetically attenuated parasites (GAPs) do not require attenuation by irradiation or concomitant drug treatment. We previously developed a (Pf) GAP with deletions in , , and genes (PfGAP3KO) and demonstrated its safety and immunogenicity in humans.