He said 1.25 million doses will have been administered by the end of March - then one million doses on average per month between April and June. That will mean up to 40% of people over 18 will have received their first dose by the end of April, up to 64% by the end of May, and up to 82% by end of June. But Prof Ryan said: "Even with the most ambitious targets by Micheál Martin - which are based on optimistic supply - we might have half the population having a single dose of the vaccine by the middle of June". "Having half the population vaccinated by April, I don't think that's realistic....