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Published on: February 25, 2013
Inferring epidemiological parameters under an infectious phylogeography model with visitor dynamics
Albert C Soewongsono1, Ammon Thompson2, Michael J Landis1
1Department of Biology, Washington University in St. Louis, St. Louis, MO 63130.
Summary
Infectious disease outbreaks are influenced by host movement. A new model shows that during the early SARS-CoV-2 pandemic in Europe, returning travelers were more likely to introduce the virus than visitors were to spread it abroad.
Area of Science:
- Epidemiology
- Mathematical Biology
- Phylogeography
Background:
- Infectious diseases spread through host movement, complicating outbreak analysis.
- Distinguishing between pathogen introduction by returning travelers versus visitors is challenging.
Purpose of the Study:
- To develop a phylogeographic model incorporating visitor dynamics for pathogen spread.
- To analyze the role of short-term travel in disease transmission during outbreaks.
Main Methods:
- Developed a phylogeographic model based on an epidemiological compartment model with visitor dynamics.
- Utilized stationary properties for a computationally tractable phylogenetic approximation.
- Derived mathematical conditions for the approximation's accuracy.
Main Results:
- SARS-CoV-2 was more frequently "pulled" into home countries by returning travelers than "pushed" abroad by visitors in early European outbreaks.
- Visitor models with short trips suggest alternative migration models may underestimate outbreak magnitudes.
Conclusions:
- Host movement dynamics, particularly short-term travel, are crucial for accurate epidemiological modeling.
- Phylogeographic models incorporating visitor dynamics offer new insights into disease spread patterns.
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