Lifecycle of the malaria parasite. After a human host is infected by the mosquito vector immature malaria parasites known as sporozites migrate to the liver where they invade hepatocytes and mature into schizonts, which then rapidly multiply into merozoites. After a 10 to 14 day incubation period, the hepatocytes rupture and thousands of merozoites emerge. Merozoites then invade erythrocytes where they extensively remodel their host cell, including exporting PfEMP1 to the red blood cell surface. Merozoites can continue in the asexual cycle or may develop into sexual stage gametocytes capable of infecting a mosquito and beginning the cycle anew. (Reproduced with permission from Figure 14-8 in DeFranco AL, Locksley RM, Robertson M: Immunity: The Immune Response in Infectious and Inflammatory Disease. Oxford: Oxford University Press; 2007.).