People over 40 are expected to be included in an updated booster programme to be announced this week.
The government's looking to speed up the delivery of third shots due to concern over the Omicorn variant.
It's aiming to have 1.5 million third doses administered before Christmas.
UCC Professor of Immunovirology, Liam Fanning, says a faster rollout of boosters is needed to deal with the Omicron threat.
Meanwhile t British Health Secretary says the Omicron variant's spreading there at a "phenomenal rate".
Boosters are to be offered to everyone over 18 in England from this week and a major logisitcal campaign's underway to ensure all adults who want one get one by the end of this month.
Sajid Javid says 10 people are now in hospitals across England with Omicron.
He says they're in a race against time against the variant.