Epidemiological impacts of age structures on human malaria transmission

TL;DR

This paper extends an age-structured malaria transmission model to derive epidemiological insights, highlighting the importance of age and immunity in understanding disease dynamics and informing control strategies.

Contribution

It generalizes existing epidemiological results to include age structure, providing a more detailed understanding of malaria transmission dynamics.

Findings

Generalized epidemiological results to age-structured models

Quantified impact of neglecting age and immunity variables

Discussed parameter values for human and mosquito populations

Abstract

Malaria is one of the most common mosquito-borne diseases widespread in tropical and subtropical regions, causing thousands of deaths every year in the world. In a previous paper, we formulated an age-structured model containing three structural variables: (i) the chronological age of human and mosquito populations, (ii) the time since they are infected, and (iii) humans waning immunity (i.e. the progressive loss of protective antibodies after recovery). In the present paper, we expand the analysis of this age-structured model and focus on the derivation of entomological and epidemiological results commonly used in the literature, following the works of Smith and McKenzie. We generalize their results to the age-structured case. In order to quantify the impact of neglecting structuring variables such as chronological age, we assigned values from the literature to our model parameters. While some parameters values are readily accessible from the literature, at least those about the human population, the parameters concerning mosquitoes are less commonly documented and the values of a number of them (e.g. mosquito survival in the presence or in absence of infection) can be discussed extensively.