Four-tier response system and spatial propagation of COVID-19 in China by a network model

TL;DR

This study models China's four-tier COVID-19 response system using a networked SEAIR model to evaluate lockdown and social distancing effectiveness across cities, highlighting the importance of staged policies for epidemic control and social stability.

Contribution

It introduces a staged, weighted network model based on China's four-tier response system to assess intervention effectiveness and infection risks during COVID-19.

Findings

Level I response is crucial for high-risk cities to control outbreaks.

Staggered release policies effectively prevent resurgence and support economic stability.

Lockdown and social distancing significantly reduce infection spread.

Abstract

In order to investigate the effectiveness of lockdown and social distancing restrictions, which have been widely carried out as policy choice to curb the ongoing COVID-19 pandemic around the world, we formulate and discuss a staged and weighed networked system based on a classical SEAIR epidemiological model. Five stages have been taken into consideration according to four-tier response to Public Health Crisis, which comes from the National Contingency Plan in China. Staggered basic reproduction number has been derived and we evaluate the effectiveness of lockdown and social distancing policies under different scenarios among 19 cities/regions in mainland China. Further, we estimate the infection risk associated with the sequential release based on population mobility between cities and the intensity of some non-pharmaceutical interventions. Our results reveal that Level I public health emergency response is necessary for high-risk cities, which can flatten the COVID-19 curve effectively and quickly. Moreover, properly designed staggered-release policies are extremely significant for the prevention and control of COVID-19, furthermore, beneficial to economic activities and social stability and development.