FIGURE 2.

Circadian Influence on Host‐Parasite Interactions. (A) The intraerythrocytic developmental cycle (IDC) of malaria‐causing Plasmodium parasites is rhythmic, generally occurring in multiples of 24 h, depending on the Plasmodium species. Misalignment of the IDC schedule relative to host circadian rhythms imposes fitness consequences for parasites. ⁷⁰ (B) Trypanosoma brucei parasites, which cause Human African Trypanosomiasis, invade brain regions involved in circadian regulation such as the hypothalamus, disrupting host circadian‐regulated processes including sleep, body temperature and hormone secretion. ⁹⁴ , ¹⁰⁰ (C) Time of day of infection with Leishmaniasis‐causing Leishmania parasites affects the magnitude of the inflammatory response, due to the circadian regulation of host immunity. ⁵⁵ , ⁵⁶ Rodents infected at night exhibit greater parasitic burden than those infected during the day due to a higher number of circulating macrophages exposed to parasites at night, leading to increased levels of cytokines and greater recruitment of neutrophils to the site of infection, which are invaded by parasites. Created in Biorender.com