COVID-19: One-dose vaccine for the whole population first and repeat later or TWO-dose vaccine early

COVID-19: One-dose vaccine for the whole population first and repeat later or TWO-dose vaccine early on?

Health officials have started mass vaccination against COVID-19 on a two-dose regimen with a short interval between two doses in Canada.

Some have raised concerns and called for a single dose vaccination first for the entire population and for the second dose to be repeated after completing the first dose.

Critics disagree, referring to the approval and lack of data. While true, this is a policy/epidemiological decision, and the required data already exists.

We need to establish immunity at the population level as quickly as possible. I ran two models under two regimes (Figure). See regimens and assumptions in the comment below.

As can be seen, if we vaccinate the entire population first with one dose and then start the second dose, subject to assumptions, we will achieve the population-level immunity sooner. --- It can prevent more cases at earlier stages and save lives.

PLEASE KINDLY CHANGE THE REGIMEN!

--- I can provide model details upon request of health authorities.