A member of the Government's COVID-19 Advisory Group says a new Omicron-specific COVID-19 vaccine could be given along with the seasonal flu shot.
Professor Luke O'Neill says he expects recommendations on a winter vaccine programme to emerge soon.
It comes amid a growing number of cases and increased hospitalisations.
Some 776 people are in hospital with the virus on Wednesday - an increase of 25 on Tuesday.
There are 31 people in ICU being treated for the disease, which is an increase of three.
Trinity College Dublin immunologist Luke O'Neill told Pat Kenny anyone due for a booster should take it.
"If you're eligible go and get one - because over half the people in hospital at the moment with COVID haven't had their booster.
"And the most sick people in hospital with COVID are unvaccinated.
"So in other words: if you're called go and get your booster.
"If you're over 65, you'll get the second booster - or if your immune system is weakened - they're the groups at the moment that are eligible."
Prof O'Neill reiterates that the vaccine prevents severe illness, but not infection.
"The evidence mounts month, by month, by month - the vaccines are working and stopping severe disease.
"I guess one confusion is you can still get infected, as we know, if you're vaccinated.
"But the truth is the vaccines stop you getting really sick".
And he says work is continuing, by both the COVID Advisory Group and National Immunisation Advisory Committee, on plans for more vaccine roll-outs.
"By the end of July, the expectation is that the [US] FDA and the EMA will approve the new Omicron vaccine.
"So if that happens, that would be the one that would be available from September.
"More than likely with the flu shot - is one idea that they're thinking about at the moment.
"I would expect strong recommendations on the vaccine campaign for the winter to emerge soon enough".
He adds: "Omicron is five-times more likely to reinfect you than Delta, you see.
"There's an amazing fact that's been uncovered, they're studying it - so therefore in other words, this really infectious variant has arisen that can breakthrough and infect people".