Mathematical Modeling of Malaria Infection with Innate and Adaptive Immunity in Individuals and Agent-Based Communities

Department of Mathematics, Case Western Reserve University, Cleveland, Ohio, United States of America.
PLoS ONE (Impact Factor: 3.23). 03/2012; 7(3):e34040. DOI: 10.1371/journal.pone.0034040
Source: PubMed


Agent-based modeling of Plasmodium falciparum infection offers an attractive alternative to the conventional Ross-Macdonald methodology, as it allows simulation of heterogeneous communities subjected to realistic transmission (inoculation patterns).
We developed a new, agent based model that accounts for the essential in-host processes: parasite replication and its regulation by innate and adaptive immunity. The model also incorporates a simplified version of antigenic variation by Plasmodium falciparum. We calibrated the model using data from malaria-therapy (MT) studies, and developed a novel calibration procedure that accounts for a deterministic and a pseudo-random component in the observed parasite density patterns. Using the parasite density patterns of 122 MT patients, we generated a large number of calibrated parameters. The resulting data set served as a basis for constructing and simulating heterogeneous agent-based (AB) communities of MT-like hosts. We conducted several numerical experiments subjecting AB communities to realistic inoculation patterns reported from previous field studies, and compared the model output to the observed malaria prevalence in the field. There was overall consistency, supporting the potential of this agent-based methodology to represent transmission in realistic communities.
Our approach represents a novel, convenient and versatile method to model Plasmodium falciparum infection.

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    • "Stochasticity is incorporated ad hoc into the models by the emergence of new variants (which are not recognized by immune system) at random times, usually driven by a Poisson process (see Nowak and May, 2000 and references therein). Very recently Gurarie et al. (2012) implemented a discrete time computer model for the case of malaria. This modeling approach, termed agent-based, consists of a set of coupled difference equations that describe the transition between successive iterations of the parasite population (i.e. "

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    • "Very recently Gurarie et al. (see ref. [18]) implemented a discrete time computer model for the case of malaria. This modeling approach, termed agent-based, consists in a set of coupled difference equations that describe the transition between successive iterations of the parasite population (i.e. "
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