Population-level protection of susceptibles when a sufficient fraction is immune — R_effective = R₀(1 – p) < 1 when p > 1 – 1/R₀. Enables targeted vaccination strategies and explains decades-long local elimination of measles/polio.
Population-level protection of susceptibles when a sufficient fraction is immune — R_effective = R₀(1 – p) < 1 when p > 1 – 1/R₀. Enables targeted vaccination strategies and explains decades-long local elimination of measles/polio.