Reproductive Strategies of the Malaria Parasite

Abstract

In spite of its tiny size and its apparent simply life cycle, several recent studies have shown that malaria parasites and their close relatives are able to modify in a relatively complex way their reproductive strategies. Malaria parasites are able to change population sex ratios to optimise reproductive success according to postulates of ‘local mate competition’ theory but also to assure fertilisation following predictions of ‘fertility insurance’ hypothesis. In addition, other potential reproductive strategies of these parasites, as multiple erythrocytic infections, are more probably a defensive mechanism of hosts than a parasitic adaptation. Malaria parasites adapt to environmental circumstances including hosts defences and number of competing parasite lineages present in the host to maximise reproductive and transmission success. The knowledge of these adaptive mechanisms will allow advances in the fight against malaria parasites. Key Concepts: Malaria parasites adapt to hosts responses and parasite competition by changing sex ratios in a way that maximise reproductive and transmission success. Multiple erythrocytic invasions are not a parasite reproductive strategy but could be a defensive mechanism of hosts.