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Extreme COVID-19 waves reveal hyperexponential growth and finite-time singularity
Induja Pavithran1, R I Sujith2
1Department of Physics, Indian Institute of Technology Madras, Chennai 600036, India.
Chaos (Woodbury, N.Y.)
|April 30, 2022
Summary
Early COVID-19 waves exhibit faster-than-exponential, hyperexponential growth, not simple exponential spread. This finding suggests stricter interventions and improved epidemic modeling for future outbreaks.
Area of Science:
- Epidemiology
- Mathematical Biology
- Statistical Physics
Background:
- Coronavirus disease 2019 (COVID-19) spread rapidly worldwide.
- Understanding early transmission dynamics is crucial for effective intervention strategies.
- Exponential growth was previously considered the hallmark of initial epidemic phases.
Purpose of the Study:
- To investigate the early transmission dynamics of extreme COVID-19 waves.
- To challenge the prevailing assumption of purely exponential early growth.
- To develop a more accurate mathematical model for epidemic forecasting.
Main Methods:
- Analysis of COVID-19 transmission data.
- Application of power-law models to describe growth patterns.
- Identification of hyperexponential growth and log-periodic oscillations.
Main Results:
- COVID-19 waves demonstrate unbounded growth and finite-time singularity, characterized by a hyperexponential power-law.
- Growth is faster than exponential, necessitating stricter public health measures.
- Log-periodic patterns were observed, potentially aiding in predicting singularities.
Conclusions:
- Early COVID-19 epidemic stages follow a hyperexponential power-law, not simple exponential growth.
- The identified patterns allow for better characterization and modeling of epidemic waves.
- Findings can improve predictions for COVID-19 and future emergent epidemics.
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