Modeling the impact of host diversity on the evolution of vector feeding preferences and implications for disease control

TL;DR

This paper presents a mathematical model analyzing how host diversity and adaptive vector behavior influence disease transmission, highlighting strategies like shortening vector infectious periods and understanding preference shifts for better control.

Contribution

It introduces a coupled host-vector model incorporating adaptive vector preferences and derives conditions affecting disease persistence and control strategies.

Findings

Shortening the vector's infectious period reduces disease prevalence.

Shifting vector preference can either amplify or reduce disease burden.

Protective measures may trigger preference shifts that impact overall disease dynamics.

Abstract

Vector-borne diseases often infect multiple host species, increasing the likelihood of disease persistence due to the presence of multiple reservoirs. Vector biting patterns and feeding preferences can shift in response to selective pressures introduced by disease control interventions, altering the dynamics of transmission. In this paper, we develop a mathematical model that couples host diversity and adaptive vector behavior with vector-borne disease transmission dynamics, focusing on a system with two hosts and a vector population exhibiting preference for one host. We derive the basic reproduction number, $R_0$, a threshold that determines the existence of two equilibria in our model, and obtain conditions that can lead to the long-term persistence of the disease. Our analysis suggests that shortening the infectious period of the vector's preferred host is an effective control strategy. We also identified a threshold that determines whether shifting vector preference toward a non-preferred host amplifies or reduces the disease burden on the primary preferred host. Our results show that protective measures for the preferred host can trigger adaptive shifts in vector preferences, reducing disease prevalence in that host. However, this shift may lead to an increase in overall host prevalence.