Abstract:Plasmodium falciparum causes the severest form of malaria which kills well over one million persons each year, chiefly children, and results in significant debilitation in hundreds of millions more. This disease has a dramatic socioeconomic impact in endemic countries and thus it is a recurring target for global health enterprises. Increased investment in existing control measures, including insecticide-impregnated bed nets, has been paired with revitalized efforts to develop an efficacious vaccine. Sequencing of the genome of P. falciparum has provided insights into the malaria parasite's complex lifecycle, which, combined with a deeper understanding of the human immune response to infection, has yielded many novel candidate vaccines during the past two decades. Most notable of these is RTS,S which has shown great promise over a long development process, becoming the first candidate vaccine against human malaria to advance to phase III clinical trials. Hence, there is optimism that in the near future RTS,S may become the first ever licensed vaccine against a parasitic disease in humans. However, this is qualified by the need for a better knowledge of its mechanism of protection and questions raised over its long-term therapeutic capacity. While the availability of RTS,S as a validated commercial product is not guaranteed, it is likely to contribute to the continuing campaign against malaria, if only as a forerunner to a fine-tuned second generation vaccine.