COVID-19 Case and Excess Mortality Analysis

Published:

Analysis of the COVID-19 Case Rate and Excess Mortality Rate by Pandemic Wave


๐Ÿ“Š COVID-19 Pandemic Wave Analysis in the U.S.

Team Members: Shuoyuan Gao, Yiqiao Zhu
Course: BIOS 620 โ€” Introduction to Health Data Science
Institution: University of Michigan School of Public Health
GitHub Repository: Analysis-of-the-COVID-19


๐Ÿ” Project Overview

This project analyzes the evolution of COVID-19 case and excess mortality rates across three major pandemic waves in the United States from January 2020 to April 2025. Using state-level weekly data on confirmed cases, total deaths, and expected deaths, we built models to quantify and forecast the impact of the pandemic.

We investigated:

  • Wave identification using time series plots of case, death, and excess mortality rates.
  • State-level variation in severity during each wave.
  • Modeling virulence using case fatality rates (CFR).
  • Cross-wave prediction using linear, LOESS, and spline models.

๐Ÿ“ˆ Key Findings

  • Wave 1 (Marโ€“Jun 2020): Highest CFR (4.5%) and Northeast hardest hit.
  • Wave 2 (Oct 2020โ€“Feb 2021): Deadliest wave with widespread impact.
  • Wave 3 (Julโ€“Oct 2021): Lower CFR due to improved healthcare and vaccination, but regional mortality remained high.

Model Insight: Nonlinear models (e.g., splines, LOESS) outperformed linear models in predicting excess mortality, especially when trained on one wave and tested on another.


๐Ÿ“„ Report Access

๐Ÿ“˜ Final Report (PDF) ๐Ÿ—‚๏ธ GitHub Repository
๐Ÿ“ Wave-specific metrics, mortality maps, CFR charts, and model comparison plots included in the full report.


๐Ÿงช Tools & Methods


๐Ÿง  Acknowledgements

This project was completed for BIOS 620 at the University of Michigan. We thank Professor Dylan Cable and our GSI Yize Hao for their support and guidance.