학술논문

Spatial effects in parasite-induced marine diseases of immobile hosts
Document Type
article
Source
Royal Society Open Science, Vol 9, Iss 8 (2022)
Subject
infectious disease epidemiology
mathematical modelling
individual-based model
basic reproduction number
spatial epidemics
marine disease spreading
Science
Language
English
ISSN
2054-5703
Abstract
Emerging marine infectious diseases pose a substantial threat to marine ecosystems and the conservation of their biodiversity. Compartmental models of epidemic transmission in marine sessile organisms, available only recently, are based on non-spatial descriptions in which space is homogenized and parasite mobility is not explicitly accounted for. However, in realistic scenarios epidemic transmission is conditioned by the spatial distribution of hosts and the parasites' mobility patterns, calling for an explicit description of space. In this work, we develop a spatially explicit individual-based model to study disease transmission by waterborne parasites in sessile marine populations. We investigate the impact of spatial disease transmission through extensive numerical simulations and theoretical analysis. Specifically, the effects of parasite mobility into the epidemic threshold and the temporal progression of the epidemic are assessed. We show that larger values of pathogen mobility imply more severe epidemics, as the number of infections increases, and shorter timescales to extinction. An analytical expression for the basic reproduction number of the spatial model, [Formula: see text], is derived as a function of the non-spatial counterpart, R0, which characterizes a transition between a disease-free and a propagation phase, in which the disease propagates over a large fraction of the system.