Influence of the transmission function on a simulated pathogen spread within a population
T Hoch1, C Fourichon, A-F Viet
1UMR708 Gestion de la Santé Animale, ENVN, INRA, Atlanpole Chantrerie, Nantes, France. hoch@vet-nantes.fr
Epidemiology and Infection
|December 8, 2007
Summary
This study explores how different mathematical functions impact simulated pathogen spread using a Susceptible-Infectious-Recovered (SIR) model. The choice of transmission function significantly affects disease dynamics, especially in changing populations.
Area of Science:
- Epidemiology
- Mathematical Biology
- Infectious Disease Modeling
Background:
- The horizontal transmission function is crucial for epidemiological models.
- Understanding transmission dynamics is key to predicting and controlling pathogen spread.
Purpose of the Study:
- To investigate the influence of various transmission functions on simulated pathogen spread.
- To analyze the biological relevance and impact of different functions within an SIR model.
Main Methods:
- Utilized a theoretical Susceptible-Infectious-Recovered (SIR) model for simulations.
- Examined different transmission functions selected from existing literature.
- Performed analytical studies to corroborate simulation findings.
Main Results:
- Different transmission functions led to varied equilibrium values for the number of infectious individuals (NI) in constant populations.
- In increasing populations, functions behaved as density-dependent (DD) or frequency-dependent (FD), affecting NI exponentially.
- Analytical results confirmed simulation outcomes.
Conclusions:
- The selection of transmission functions, particularly DD versus FD, critically influences simulated pathogen spread.
- Careful consideration of transmission functions is essential when modeling disease dynamics in variable population sizes.
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