Minister for Health Stephen Donnelly has said his department is watching closely the recent rise in Covid-19 hospitalisations.
He has urged people to take up their booster vaccine. Just one third of those aged 65 years and older have got their second booster jab, he said.
People over 65 and anyone aged over 12 with a weak immune system are eligible for a second booster dose.
Anyone aged 12 and over, who has not yet received a first booster dose, can book an appointment for one through the HSE portal.
The minister said the health system is set up for another wave but added that it would affect hospital waiting lists and patients waiting.
Meanwhile, an immunologist has said Covid-19 infections are on the rise and that it is "astonishing" how infectious the Omicron variant is.
Cliona O'Farrelly, Professor of Comparative Immunology and Biochemistry at Trinity College Dublin, said: "It really is astonishing. It is very difficult to avoid it. It's like the common cold ... once it gets going at all, everybody gets it."
Her comments come as the number of patients in hospital with Covid-19 is 355, an increase of 44 on yesterday's figure.
Of those, 22 people are being treated in intensive care units with the virus, down two on yesterday.
Speaking on RTÉ's Today with Claire Byrne, Prof O'Farrelly said most people will not know that they are infected or will have very mild symptoms.
"The big worry is what it does to the hospitals, so that is a concern."
She said the level of infection is on the rise and "you can see our change in behaviour over the last few weeks. We are longing, all of us, longing to get out and travel."
'No need for panic at the moment'
However, a specialist registrar in infectious diseases at St James's Hospital in Dublin has said that at the moment there is no reason for overwhelming concern about the rising Covid-19 hospital cases.
Dr Liam Townsend said it was not surprising given Ireland has relaxed a lot of measures and life has returned to normal in many ways.
Dr Townsend said it was important to note that many of the patients in hospital who are detected to have Covid-19 may not be there primarily due to the disease.
He said that Ireland is lucky as this is unlike prior waves.
Dr Townsend said doctors are seeing a lot of mild disease, or people with Covid that is causing complications on another illness they already have, rather than the primary reason for them being quite unwell.
He said there was no need for panic at the moment and that it was important for people to get their boosters, adding that those who have symptoms should get tested and follow the public health advice.
Rise in patients on public waiting lists
Meanwhile, there has been a further rise in the number of patients on public hospital waiting lists.
The latest figures published today show that in May, there were over 851,700 waiting for treatment, or a first meeting with a consultant for an outpatient appointment.
The number of patients waiting for a first outpatient appointment is 624,444.
The overall figure is up by over around 1,700 patients on the April figures, from the National Public Treatment Purchase Fund.
Stephen McMahon of the Irish Patients Association has said that it is important to note that the NPFF data is not for the full month of May as it ends on 26 May.
Additional reporting Fergal Bowers
