This type of vaccine targets the parasite as it infects the liver.
First-generation malaria vaccines aim to protect against clinical malaria by preventing the parasite from progressing to blood stage infections. Known as pre-erythrocytic stage vaccines, they target the circumsporozoite (CS) protein. The CS protein is the dominant protein on sporozoites, the parasite form that enters a person's blood stream following the bite from an infectious mosquito, and migrates to the liver where it matures and begins a prolific multiplication process that leads to symptoms of clinical malaria. These vaccines elicit an immune response that would either prevent the sporozoite entering the liver and/or attack the infected liver cell if infection does occur.