Smoking epidemic eradication in a eco-epidemiological dynamical model

Smoking is perceived as a major epidemic with regard to mortality. Modelling is a major tool used to obtain insight in the dynamics and possible solutions to decrease or even eradicate this epidemic. Most models on smoking consider the epidemiological context explicitly, in which smoking is regarded as an ‘infectious disease’, in which individuals ‘infect’ each other. However, the population dynamics are often ignored, while these occur at roughly the same timescale as smoking, and hence should explicitly be considered in the modelling of smoking. We present a simple but dynamical eco-epidemiological model. The model formulation consists of a resource-population dynamic part coupled to an epidemiological part resembling a SIR type model for the three compartments: non-smokers, smokers and ex-smokers. The coupling is via birth of non-smokers and death of the three classes with different death rates. The final four-dimensional system of ordinary differential equations are studied using brute force simulations for the short term dynamics and bifurcation analysis for the long-term dynamics. Due to a feed-back mechanism of the two coupling terms there is a codim-two tangent-transcritical bifurcation. This leads to bi-stability of one smoker endemic interior equilibrium and a smoker free boundary equilibrium. Changing parameters beyond the emerging tangent bifurcation leads on the short term to eradicating smoking. We consider the Netherlands in this paper for parametrization, but the modelling approach may be generally applicable.

► The smoking epidemic can be modeled using SIR modelling.
► However, the effects of smoking occur at roughly the same timescale as human population dynamics, coupling epidemiology to ecology.
► The eco-epidemiological dynamic model of smoking shows simultaneous existence of a smoker epidemic and smoker free steady state.
► Changes in policy sensitive parameters can lead to eradication of the smoking epidemic in the model.