Vaccination Strategy

Pre-immunize a portion of the population through vaccination. Demonstrates herd immunity threshold where epidemic fails to take off.

Susceptible: 0
Vaccinated: 0
Infected: 0
Recovered: 0
Time: 0
Herd Immunity: When vaccination coverage exceeds critical threshold (1 - 1/R₀), epidemic cannot spread.
Susceptible
Vaccinated
Infected
Recovered