| Malaria caused by Plasmodium falciparum is a potentially fatal infection. Understanding how the extensive genetic polymorphism of the parasite affects the acquisition and maintenance of immunity is a prerequisite for the development of efficacious control tools such as vaccines. In our previous studies, we have shown that persistent asymptomatic multiclonal infections predict a reduced risk of disease in high transmission settings. The aim of this project is to further establish how the genetic diversity of P. falciparum infections affects protective immunity to malaria. We will investigate polymorphisms in P. falciparum antigen genes, i.e. genes under immune selection, in individuals with different levels of exposure and immunity both within and between geographical areas, and identify potential ?hotspots? of transmission. The genetic diversity of P. falciparum infections will be related to the breadth and magnitude of antibody responses directed to a panel of several P. falciparum antigens. The longevity of immune responses (antimalarial antibody and memory B cell responses) will be studied. The project includes well defined and closely monitored cohorts living in areas of different transmission in Kenya, Tanzania and Mali, as well as Swedish travellers who experience malaria for the first time. The project will contribute to the understanding of the molecular epidemiology of P. falciparum and the acquisition and maintenance of protective immunity against malaria. |
