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Published on: June 30, 2023
Self-organized wavy infection curve of COVID-19
1Kyushu University, Fukuoka, 819-0395, Japan. t.odagaki@kb4.so-net.ne.jp.
Abstract:
Exploiting the SIQR model for COVID-19, I show that the wavy infection curve in Japan is the result of fluctuation of policy on isolation measure imposed by the government and obeyed by citizens. Assuming the infection coefficient be a two-valued function of the number of daily confirmed new cases, I show that when the removal rate of infected individuals is between these two values, the wavy infection curve is self-organized. On the basis of the infection curve, I classify the outbreak of COVID-19 into five types and show that these differences can be related to the relative magnitude of the transmission coefficient and the quarantine rate of infected individuals.
Insights
Fluctuations in COVID-19 isolation policies in Japan created wavy infection curves. Self-organized waves emerged when the removal rate of infected individuals fell between two infection coefficient values.
Area of Science:
- Epidemiology
- Mathematical Modeling
- Public Health Policy
Background:
- The COVID-19 pandemic presented complex challenges in controlling viral spread.
- Understanding the dynamics of infection curves is crucial for effective public health interventions.
- Japan's COVID-19 trajectory exhibited unique wavy patterns that warranted investigation.
Purpose of the Study:
- To investigate the causes behind the wavy COVID-19 infection curves observed in Japan.
- To model the impact of fluctuating isolation policies on disease transmission.
- To classify COVID-19 outbreak patterns based on epidemiological parameters.
Main Methods:
- Utilized the Susceptible-Infected-Quarantined-Removed (SIQR) mathematical model.
- Assumed the infection coefficient as a two-valued function dependent on daily new cases.
- Analyzed the relationship between the removal rate and infection coefficient for self-organized wave emergence.
Main Results:
- Demonstrated that fluctuating government and citizen adherence to isolation measures drives wavy infection curves.
- Identified that self-organized wavy curves occur when the infected removal rate is between two specific infection coefficient values.
- Classified COVID-19 outbreaks into five distinct types based on infection curve characteristics.
Conclusions:
- Policy fluctuations and public compliance significantly influence COVID-19 transmission dynamics.
- The interplay between transmission rates and quarantine effectiveness dictates outbreak patterns.
- The study provides a framework for understanding and potentially managing diverse COVID-19 outbreak scenarios.
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