CHRONOBIOLOGY OF PLASMODIUM-CHABAUDI CHABAUDI - ANALYSIS OF HOURLY RECORDED TOTAL AND DIFFERENTIAL PARASITEMIA DURING A SCHIZOGONIC CYCLE

Detailed total and differential parasitaemia curves of asexual plasmod ium chabaudi chabaudi erythrocytic stages were recorded and analysed. Female, inbred, CBA/Ca mice were infected with the virulent IP-PC1 str ain after in vitro synchronization of the parasites. Thin blood smears were made on an hourly basis. and the total and differential parasita emio of ring forms. trophozoites and schizonts were counted after Giem sa staining. These curves reveal information that remains hidden when less detailed curves are examined: the duration and periodicity of the schizogonic cycle, the existence of a plateau, indications of a schiz ont withdrawal from the peripheral blood, the timing of the rise of th e parasitaemia at each schizogony, and the invasion rate of the merozo ites. In the perspective of developing a rational and efficient strate gy far chronotherapy of malaria, such information should be taken into account.