The head of the HSE says Ireland's population should be fully vaccinated by the end of August.
Paul Reid says while the pandemic remains a concern, and hospitalisations rise, we are "extremely close" to full vaccination.
Latest figures show 89% of the adult population - 3.2 million people - have received one vaccine dose.
While 76% of the adult population - 2.85 million people - are now fully vaccinated.
Mr Reid told Newstalk Breakfast: "Certainly during August we expect that the vast majority of the Irish adult population who come forward for a vaccine will have received it.
"We'll be certainly by the end of August/early September have completed the adult population.
"And probably about four weeks ahead of where we thought we would be".
On the portal for 12 to 15-year-olds, which opens next Thursday, he says vaccines should start early the following week.
Confusion over COVID regulations 'a reality'
While Mr Reid says confusion over COVID regulations is 'a reality that we deal with'.
He was speaking after the Attorney-General intervened in a debate around outdoor events.
While Fáilte Ireland has re-drafted guidelines to the hospitality sector, after the Attorney-General said it was legal to host outdoor events of up to 200 people.
Mr Reid says: "I think we've had to experience many times like this over the past 16 months, and it's just a reality that we all deal with.
"Throughout the whole pandemic there's been various times, various representative bodies, various sectors, various groups, we've had political issues where there tend to be contrasting views, interpretations that can tend to be one public health measure contrasting against another.
"From our perspective in the HSE, we've always been saying to people we have to take the whole piece in the round, or response in the round, which has been really good.
"Our concern is that people do get distracted, get confused, get less committed and do drop their guard.
"And we are so close to completing this vaccination programme and so close to protecting so many people.
"But equally we're so close to losing it very quickly".
Referring to footage, which appears to show customers dancing on tables and drinking at the bar while not wearing masks in a Kilgarvin pub owned by Kerry TD Danny Healy-Rae, Mr Reid says: "There's been many instances across the country where regulations have been breached.
"From a HSE perspective what I would always say is we're looking at some very sick people coming into our hospitals.
"We're still seeing very rising cases and steadily increasing every day.
"July was our highest month of the whole pandemic for the amount of testing we did - so the virus is out there, it's still transmitting".