LINKING POPULATION DYNAMICS AND DISEASE MODELS FOR MULTI-HOST PATHOGEN SYSTEMS: IMPLICATIONS FOR PATHOGEN AND SPECIES INVASION

Abstract

We consider models for the spread of disease in one or two species where density-dependent population dynamics can range from affecting primarily reproduction and juvenile survival to affecting death rates of adults. We show that disease and competition (both intra- and inter-specific) can interact to change the dynamics of a system, resulting in changes in species density, disease invasion and prevalence. Additionally, we show that the mechanism of competition between and within species can affect the ability of a disease to spread and persist. If density dependence acts only on reproduction and juvenile survival rates, disease is more likely to persist, while for the same system if competition acts solely on the survival rate of adults the disease is less likely to successfully invade. This has implications both for conservation and public health, especially as climate change and invasive species change community structure and as zoonotic diseases become more important.