Chronobiology: A Challenge To Malaria Definition And Parasitaeemia

Abstract

Periodic temporal variations in peripheral blood parasite density were evaluated in a simple parallel study of symptomatic young men and women in an endemic village in eastern Nigeria. Our main objective was to find the effect of chronobiology, on malaria definition and parasitaemia. Parasite densities were recorded four square times in each study subject at four hours interval. A total of fifty-one subjects with signs and symptoms suggestive of malaria were enrolled. Amplitude of variations of more than ten times was observed between the four hour interval. Results showed that frequent negative smears were observed mainly in the morning and evening hours while the highest parasite densities occurred at noon. Results further showed that there was significant difference between the parasite densities observed around noon and morning or evening period. Profiles of individual parasite densities are presented. These variations which are probably due to sequestration-release mechanism or any other mechanisms remain to be elucidated.

Keywords: Chronobiology, Circadian, Cryptochrome, Sequestration.