A pivotal test of malaria vaccine is set to begin. Can it live up to its promise?

Over the next four years, the experiences of these countries will help the WHO determine if RTS,S can be effectively used, and whether it will deliver the nearly 40 percent decrease in malaria infections seen in an earlier Phase 3 clinical trial.To see whether a new malaria vaccine, RTS, is effective, the World Health Organization (WHO) and partners have devised a limited rollout of the vaccine in Malawi followed by Ghana and Kenya.