The one-millionth dose of the Covid-19 vaccine is due to be administered in Ireland today.
The Government had previously aimed to get 1.25 million doses given to people by the end of March, however, there were supply issues.
Meanwhile, nine further Covid-19 related deaths have been recorded by the Department of Health and 443 new cases of the disease were reported.
The five-day moving average number of cases now stands at 463, which is almost 15 percent lower than last week.
One in six adults in Ireland have received at least one dose of a Covid-19 vaccine, acccording to Minister for Health Stephen Donnelly.
Mr Donnelly also said that Ireland currently has one of the lowest rates of Covid-19 in Europe.
It comes as the health service in Ireland plans to ramp up its vaccine programme following months of setbacks and missed targets.
Despite plans to administer one million doses of Covid-19 vaccines throughout April, the Government revised down its target to around 860,000 vaccines.
On Tuesday, Mr Donnelly tweeted: “One in six adults in Ireland has now received at least one dose of a Covid vaccine.
“The no (number) of people with Covid in ICUs has fallen by about 75% since peak in late January.
“We’ve one of the lowest rates of Covid-19 in Europe now. We’re making huge progress.”