Further changes to the vaccine roll-out plan could be on the cards as health officials review the use of AstraZeneca.
A recommendation is expected to be made to government this evening.
Multiple reports this afternoon suggest the use of AstraZeneca is to be restricted to people aged 60 and over.
Ireland would be the latest EU country to limit the use of AstraZeneca after reports of rare blood clots linked to that vaccine.
One of the key questions would be what will happen for people under 60, maybe with an underlying condition, who've already been given one dose of AstraZeneca.
Trinity College Immunologist Luke O'Neill says other countries are also grappling with that.
Over-60s
If NIAC does recommend use in over-60s only it presents a serious headache for the government logistically.
There are still hundreds of thousands of over-60s yet to be vaccinated - with the over-70s group likely to be finished around mid-May.
Over the next three months 20 per cent of the vaccines due to arrive in Ireland are from AstraZeneca, which gives some scope to find a workaround that will cause minimal impact to the roll-out timeframes.
