Figure 1.

The sexual gametocytes transmit infection and complete the life cycle from humans to mosquitoes. 2–6: The sporogonic stages are where gametes form oocysts in the mosquito mid-gut then proceed to become sporozoites in the salivary glands. 7: The infective sporozoites are inoculated into humans during a mosquito bite.8A and 9A: Sporozoites travel to the liver and pre-erythrocytic schizogony occurs here. The resulting tissue schizonts rupture and releases merozoites into the bloodstream; causal prophylactic drugs act here. 8B and 9B: In P. vivax and P. ovale, some sporozoites will separately differentiate into dormant hypnozoites. When triggered to ‘wake up’, the latent hypnozoites will undergo pre-erythrocytic schizogony; ‘radical cure’ targets this life-cycle stage. 10: Asexual intraerythrocytic schizogony is the blood stage of infection when symptoms occur and where blood schizontocidal drugs act.This figure was reproduced and modified from Figure 1 in Peters, 1999,³ ‘based on an original figure by Andrea Darlow’ under SAGE publications licence number 4519190237646.