The role of initial inoculum on epidemic dynamics
1Department of Mathematical Sciences, University of Bath, Bath, BA2 7AY, UK. kajw@maths.bath.ac.uk
Journal of Theoretical Biology
|May 30, 2006
Summary
The initial spatial distribution of pathogen inoculum significantly impacts epidemic transient dynamics in agricultural and ecological systems. Understanding primary versus secondary infection balances offers simple predictive rules for epidemiologists.
Area of Science:
- Epidemiology
- Mathematical Biology
- Ecology
Background:
- Transient dynamics are crucial in epidemics within agricultural and ecological systems subject to disturbances.
- Pathogen spread is influenced by factors like diffusion, advection, and host-pathogen interactions.
Purpose of the Study:
- To investigate the effect of initial pathogen inoculum distribution on epidemic transient dynamics.
- To analyze how spatial factors and infection types influence epidemic behavior in host-pathogen systems.
Main Methods:
- Utilized a mathematical host-pathogen model for sessile hosts with mobile pathogens.
- Employed mathematical techniques including perturbation analysis and non-dimensionalization.
- Examined isolated and multi-patch systems with varying boundary conditions.
Main Results:
- Identified two key parameter groups influencing transient dynamics: primary/secondary infection strength and infectivity of initial inoculum.
- Derived approximate solutions using non-dimensionalization and perturbation techniques.
- Obtained exact solutions for primary infection-only scenarios, showing dependence on initial and boundary conditions.
Conclusions:
- The initial spatial distribution of inoculum is a critical determinant of epidemic transient dynamics.
- Analysis of primary and secondary infection balances provides practical predictive rules for epidemiologists.
- Mathematical modeling offers insights into managing and predicting epidemic spread in vulnerable systems.
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