Integrated travel network model for studying epidemics: Interplay between journeys and epidemic

Area of Science:

• Network science
• Epidemiology
• Transportation science

Background:

• Globalization increases inter-city travel, raising epidemic outbreak risks.
• Current models inadequately capture the traveler's perspective in epidemic spread.
• Effective epidemic control requires understanding travel network dynamics.

Purpose of the Study:

• To develop a novel modeling framework, the integrated travel network (ITN) model, from a traveler's viewpoint.
• To analyze the impact of travel speed and frequency on epidemic propagation.
• To simulate epidemic spread in a real-world transportation network.

Main Methods:

• Constructed an integrated travel network (ITN) model incorporating node (city population, infrastructure) and link (distance, transport speed) diversity.
• Modeled round-trip journeys based on shortest travel times.
• Simulated epidemic spread on a network of 116 Chinese cities connected by high-speed rail and highways.

Main Results:

• Travel speed and frequency are critical factors influencing epidemic spread.
• Increased travel speed can either enhance or suppress epidemic spread, contingent on the infection rate.
• Increased travel frequency consistently enhances epidemic spreading.

Conclusions:

• The integrated travel network (ITN) model provides a more realistic framework for studying epidemic dynamics.
• Travel speed and frequency significantly modulate epidemic propagation, with nuanced effects of speed.
• Findings are crucial for public health policy and epidemic preparedness in interconnected societies.