SIR Epidemic Model

The classic compartmental model: Susceptible → Infected → Recovered. Drag sliders to explore how R₀ = β/γ determines outbreak size. The epidemic threshold is R₀ = 1.

dS/dt = −βSI/N | dI/dt = βSI/N − γI | dR/dt = γI

Susceptible (S)

Infected (I)

Recovered (R)

Transmission rate β 0.30

Recovery rate γ 0.10

Initial infected % 1

Population N 1000

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