Effect of vaccine deployment on R, the reproductive number, in response to vaccination strategies for COVID-19 Alpha and Delta variants.

Epidemic reproduction number as a function of vaccinated fraction of population and vaccine efficiency for each of the four presented strategies, assuming a base reproduction number of R0 = 2.5 for the COVID-19 Alpha variant and R0 = 3 for the Delta variant. Each data point (mean and standard error) is based on 20 simulations.