Analysis of COVID-19 Infection Dynamics: Extended SIR Model Approach

Caleb Traxler, Minh Ton, Nameer Ahmed, Sasha Prostota, Annie Cheng

wrongmedium confidence

Category: math.DS
Journal tier: Note/Short/Other
Processed: Sep 28, 2025, 12:56 AM
arXiv Links: Abstract ↗PDF ↗

Audit review

The paper’s core SIR-with-demography analysis is broadly correct, but its vaccination section mixes two different vaccination mechanisms: it writes the per-capita S→V flow dv/dt = p s − μ v yet states the disease-free equilibrium E0 = (1−p,0,v=p) and Rv = R0(1−p), which are only correct for newborn (at-birth) vaccination. The model solution correctly distinguishes the two parameterizations, derives the correct thresholds and equilibria for each, and provides a sound center-manifold proof of a transcritical bifurcation at R0=1. Hence, the paper contains a substantive inconsistency, while the model solution is correct and complete.

Referee report (LaTeX)

\textbf{Recommendation:} major revisions

\textbf{Journal Tier:} note/short/other

\textbf{Justification:}

The vaccination section conflates two different mechanisms, producing incorrect DFE and Rv for the written ODEs. Otherwise the SIR-with-demography analysis is standard and correct, and the empirical discussion is reasonable. Correcting the vaccination parameterization and qualifying the spiral/node classification would remedy the main issues; adding a brief center-manifold calculation would strengthen the bifurcation claim.