Epidemic models (SIR)
General · Mathematics
Study notes
Q: Disease: β = 0.3/day, γ = 0.1/day. Find R₀. Will it spread? Herd immunity threshold? R₀ = β/γ = 0.3/0.1 = 3. R₀ > 1: SPREADS (each infects 3!)! Herd immunity: 1-1/R₀ = 1-1/3 = 67% immune needed. Peak when S = 1/R₀! Final size equation! (SIR: epidemics in equations!)