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Published on: September 25, 2021
Epidemic outbreaks in two-scale community networks
Stefano Bonaccorsi1, Stefania Ottaviano2, Francesco De Pellegrini2
1Mathematics Department, University of Trento, via Sommarive 14, 38123 Povo (Trento), Italy.
This study models epidemic spread in local communities using a susceptible-infected-susceptible (SIS) model. It shows that distinct infection rates within and between communities influence epidemic outbreaks and metastable infection probabilities.
Area of Science:
- Epidemiology
- Mathematical Biology
- Network Science
Background:
- Epidemic modeling often simplifies population structures.
- Understanding community-level dynamics is crucial for predicting disease spread.
- Previous models lacked detailed community interaction parameters.
Purpose of the Study:
- To analyze a continuous-time susceptible-infected-susceptible (SIS) model with distinct intra- and inter-community infection probabilities.
- To provide a framework for describing localized, faster epidemic spread within communities.
- To express epidemic outbreak probability as a metastable infection probability.
Main Methods:
- Utilized a mean-field approximation for epidemic diffusion.
- Modeled population structure using an adjacency matrix of clusters and a vector of community sizes.
- Analyzed a continuous-time SIS model.
Main Results:
- Developed a model where infection dynamics differ within and between local communities.
- Demonstrated that community structure impacts epidemic spread rates.
- Established that epidemic thresholds depend on community size and inter-community connections.
Conclusions:
- The proposed model offers a compact description of clustered epidemic spread.
- Metastable infection probability is a key outcome influenced by network topology.
- The model provides insights into epidemic outbreaks in structured populations.
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