Plasmodium falciparum parasitaemia described by a new mathematical model

A new mathematical model of Plasmodium falciparum asexual parasitaemia is f ormulated and fitted to 35 malaria therapy cases making a spontaneous recov ery after primary inoculation. Observed and simulated case-histories are co mpared with respect to 9 descriptive statistics. The simulated courses of p arasitaemia are more realistic than any previously published. The model use s a discrete time-step of 2 days. Its realistic behaviour was achieved by t he following combination of features (i) intra-clonal antigenic variation, (ii) large variations of the variants' baseline growth rate, depending on b oth variant and case, (iii) innate autoregulation of the asexual parasite d ensity, variable among cases, (iv) acquired variant-specific immunity and ( v) acquired variant-transcending immunity, variable among cases. Aspects of the model's internal behaviour, concerning variant dynamics, as well as th e respective contributions of the three control mechanisms (iii) - (v), are displayed. Some implications for pathogenesis and control are discussed.