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Author Spotlight: Advancements in Multiplex Detection of Respiratory Viruses
Published on: November 10, 2023
Epidemic spreading on modular networks: The fear to declare a pandemic
Lucas D Valdez1, Lidia A Braunstein1,2, Shlomo Havlin1,3,4
1Department of Physics, Boston University, Boston, Massachusetts 02215, USA.
Abstract:
In the past few decades, the frequency of pandemics has been increased due to the growth of urbanization and mobility among countries. Since a disease spreading in one country could become a pandemic with a potential worldwide humanitarian and economic impact, it is important to develop models to estimate the probability of a worldwide pandemic. In this paper, we propose a model of disease spreading in a structural modular complex network (having communities) and study how the number of bridge nodes n that connect communities affects disease spread. We find that our model can be described at a global scale as an infectious transmission process between communities with global infectious and recovery time distributions that depend on the internal structure of each community and n. We find that near the critical point as n increases, the disease reaches most of the communities, but each community has only a small fraction of recovered nodes. In addition, we obtain that in the limit n→∞, the probability of a pandemic increases abruptly at the critical point. This scenario could make the decision on whether to launch a pandemic alert or not more difficult. Finally, we show that link percolation theory can be used at a global scale to estimate the probability of a pandemic since the global transmissibility between communities has a weak dependence on the global recovery time.
Insights
Increased global connectivity due to urbanization and travel heightens pandemic risk. This study models disease spread in complex networks, finding that more connecting nodes amplify pandemic probability, complicating early alert decisions.
Area of Science:
- Epidemiology
- Network Science
- Mathematical Modeling
Background:
- Global pandemics pose significant humanitarian and economic threats.
- Increased urbanization and international mobility have led to a rise in pandemic frequency.
- Accurate models are crucial for estimating worldwide pandemic probability.
Purpose of the Study:
- To propose and analyze a model for disease spread in complex, modular networks.
- To investigate the impact of 'bridge nodes' connecting communities on disease propagation.
- To understand how network structure influences pandemic potential.
Main Methods:
- Developed a disease spreading model on a structural modular complex network.
- Analyzed the effect of the number of bridge nodes (n) on disease transmission dynamics.
- Utilized link percolation theory for global-scale pandemic probability estimation.
Main Results:
- Disease spread dynamics at a global scale resemble an infectious transmission process between communities.
- Global infectious and recovery times depend on community structure and the number of bridge nodes (n).
- Increasing 'n' near the critical point leads to widespread disease but low recovery within communities.
- Pandemic probability increases abruptly as n approaches infinity, complicating alert systems.
Conclusions:
- The number of bridge nodes significantly influences global pandemic risk.
- Link percolation theory provides a viable framework for estimating pandemic probability.
- Complex network structures can lead to abrupt increases in pandemic likelihood, posing challenges for public health response.
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