Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Steps in Outbreak Investigation01:18

Steps in Outbreak Investigation

In the ever-evolving field of public health, statistical analysis serves as a cornerstone for understanding and managing disease outbreaks. By leveraging various statistical tools, health professionals can predict potential outbreaks, analyze ongoing situations, and devise effective responses to mitigate impact. For that to happen, there are a few possible stages of the analysis:
Infectious Diseases and Their Occurrence01:28

Infectious Diseases and Their Occurrence

Infectious diseases appear in populations through various transmission patterns, influenced by pathogen characteristics, population immunity, environmental conditions, and social behavior. Understanding these patterns is essential for effective public health surveillance and intervention. These categories—sporadic, outbreak, epidemic, pandemic, and endemic—help frame the nature and scope of disease events.Sporadic diseases occur irregularly and infrequently, without a predictable temporal or...
Population Growth00:57

Population Growth

Population size is dynamic, increasing with birth rates and immigration, and decreasing with death rates and emigration. In ideal conditions with unlimited resources, populations can increase exponentially, which plots as a J-shaped growth rate curve of population size against time. This type of curve is characteristic of newly-introduced invasive species, or populations that have suffered catastrophic declines and are rebounding.However, realistic environmental conditions limit the number of...
Causality in Epidemiology01:21

Causality in Epidemiology

Causality or causation is a fundamental concept in epidemiology, vital for understanding the relationships between various factors and health outcomes. Despite its importance, there's no single, universally accepted definition of causality within the discipline. Drawing from a systematic review, causality in epidemiology encompasses several definitions, including production, necessary and sufficient, sufficient-component, counterfactual, and probabilistic models. Each has its strengths and...
Exponential Equations for Modeling Growth01:26

Exponential Equations for Modeling Growth

Exponential models are essential for describing rapid, multiplicative changes in natural systems, such as population growth. When a population doubles at regular intervals, the process can be modeled using a suitable base. For instance, a bacterial culture that doubles every three hours follows the model n(t)=n0⋅2t/3, where n(t) is the population at the time t.A more general model uses the natural base e, especially for continuous growth. This takes the form n(t)=n0⋅ert, where r is the relative...
Infection01:20

Infection

When a pathogen enters the body and reproduces, it can cause an infection, damage body cells, and cause illness symptoms that eventually lead to disease. Therefore, its prevention requires breaking the chain of infection.
The chain begins with pathogens: bacteria, viruses, fungi, prions, or parasites such as protozoa helminths. These can be present on the skin as transient or resident flora, or they can be acquired from the environment. Identifying and treating the type of infection and...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Shortest-path percolation on scale-free networks.

Physical review. E·2026
Same author

Charting multidimensional ideological polarization across demographic groups in the USA.

Nature human behaviour·2025
Same author

Neighbor-induced damage percolation.

Physical review. E·2025
Same author

Leveraging spurious Omori-Utsu relation in the nearest-neighbor declustering method.

Physical review. E·2025
Same author

Scaling and universality for percolation in random networks: A unified view.

Physical review. E·2025
Same author

General theory for extended-range percolation on simple and multiplex networks.

Physical review. E·2024

Related Experiment Video

Updated: Jun 5, 2026

Inherent Dynamics Visualizer, an Interactive Application for Evaluating and Visualizing Outputs from a Gene Regulatory Network Inference Pipeline
10:44

Inherent Dynamics Visualizer, an Interactive Application for Evaluating and Visualizing Outputs from a Gene Regulatory Network Inference Pipeline

Published on: December 7, 2021

Thresholds for epidemic spreading in networks.

Claudio Castellano1, Romualdo Pastor-Satorras

  • 1Istituto dei Sistemi Complessi (CNR-ISC), UOS Sapienza and Dip. di Fisica, Sapienza Università di Roma, P.le A. Moro 2, I-00185 Roma, Italy.

Physical Review Letters
|January 15, 2011
PubMed
Summary
This summary is machine-generated.

In quenched networks, epidemic activity thresholds vanish for susceptible-infected-susceptible models due to large hubs, not scale-free properties. Susceptible-infected-removed models show finite thresholds, aligning with theory.

More Related Videos

Modeling the Functional Network for Spatial Navigation in the Human Brain
05:55

Modeling the Functional Network for Spatial Navigation in the Human Brain

Published on: October 13, 2023

Related Experiment Videos

Last Updated: Jun 5, 2026

Inherent Dynamics Visualizer, an Interactive Application for Evaluating and Visualizing Outputs from a Gene Regulatory Network Inference Pipeline
10:44

Inherent Dynamics Visualizer, an Interactive Application for Evaluating and Visualizing Outputs from a Gene Regulatory Network Inference Pipeline

Published on: December 7, 2021

Modeling the Functional Network for Spatial Navigation in the Human Brain
05:55

Modeling the Functional Network for Spatial Navigation in the Human Brain

Published on: October 13, 2023

Area of Science:

  • Epidemiology
  • Network Science
  • Statistical Mechanics

Background:

  • Epidemic models are crucial for understanding disease spread.
  • Network structure significantly influences epidemic dynamics.
  • Heterogeneous mean-field (HMF) theory is a common approach for analyzing epidemic thresholds.

Purpose of the Study:

  • To investigate epidemic model thresholds in quenched networks with power-law degree distributions.
  • To determine how network properties, particularly maximum degree, affect epidemic activity thresholds.
  • To compare model predictions with Heterogeneous Mean-Field (HMF) theory.

Main Methods:

  • Analysis of epidemic thresholds for susceptible-infected-susceptible (SIS) and susceptible-infected-removed (SIR) models.
  • Study of quenched networks characterized by power-law degree distributions.
  • Examination of the role of the maximum degree (k_max) in epidemic spread.

Main Results:

  • The activity threshold for the SIS model vanishes in the large size limit for networks with diverging k_max, contradicting HMF theory.
  • This vanishing threshold is attributed to the largest hub acting as a self-sustained source, independent of the scale-free nature.
  • The SIR model shows agreement with HMF theory, exhibiting a finite threshold on scale-rich networks.

Conclusions:

  • The presence of a vanishing or finite epidemic threshold on quenched scale-rich networks depends on whether a steady state exists.
  • The behavior of epidemic models is highly sensitive to network topology, especially the presence of high-degree nodes (hubs).
  • Further research is needed to generalize these findings to other epidemic models and network types.