This type of vaccine would target the parasite at its most destructive stage.
Blood-stage vaccine candidates target the malaria parasite at its most destructive stage—the rapid replication of the organism in human red blood cells. Blood-stage vaccines are expected to decrease the number of parasites in the blood, and in so doing, reduce the severity of disease. Evidence suggests that people who have survived regular exposure to Plasmodium develop natural immunity over time. The goal of a vaccine that contains antigens or proteins from the surface of the blood-stage parasite (the merozoite) would be to allow the body to develop that natural immunity with much less risk of getting ill. Natural immunity to parasites at the blood stage is short-lived, and an additional goal of this type of vaccine is to generate a more durable immune response without a requirement for boosting with natural infections to maintain immunity.