The winter months will be "difficult" for the health service, HSE CEO Paul Reid has said.
He said many healthcare workers are exhausted "after four waves of COVID and a cyberattack", while hospitals have also seen a rise in the number of COVID patients over the last week or so.
However, he said many measures are being put in place to support the hospital system during the winter.
The latest figures show 293 people in hospital with COVID-19, including 74 in ICU.
Meanwhile, recent days have seen a notable increase in the number of COVID-19 cases being reported daily, with around 2,000 new cases being reported on Friday and Saturday.
Mr Reid told Newstalk Breakfast said the number of patients in the hospital "is a concern for us".
However, he said it's not the same situation as we saw in January.
He said: “We are in a much different position when we see we have 92% of the adult population fully vaccinated… it’s not necessarily just a measure of caseloads on the day.
“What we have seen significantly is a rise of around 23% of those in hospital with COVID.
"As of last night, there were 293 people in hospital and 74 in ICU. 67% of people in ICU today have had no vaccination, and 3% had been partially vaccinated.
“In ICU at the moment… 58% are over the age of 50, but 40% are in the age bracket of 15-49.
"There’s a high proportion of people not vaccinated, and across all age groups."
He said COVID-19 still has a "disproportionate" impact on the hospital system as patients need to be isolated, while some hospitals potentially need to create dedicated wards when there are large numbers of patients needing treatment.
The HSE CEO said Ireland is among the world leaders when it comes to vaccination, but there's still a "real call" for unvaccinated people to come forward.
Mr Reid said COVID-19 hospitalisations have "stayed very steady" and officials would like to see the numbers going down as we head into winter.
He said: “It is going to be a difficult winter.
"You can see many some of the pressure on staff - many of them are exhausted after four waves of COVID and a cyberattack.
“We’re putting in a number of initiatives throughout winter, funded by the Government, to support the hospital system.”
One initiative includes support from private hospitals: there's already a procurement arrangement, with the HSE currently using about 1,000 bed days per week from the private system for non-COVID care.
Efforts are also underway to put in extra capacity in the public hospital system, as well as offering more community care outside of hospitals.
He said there's also work underway to stop the ever-growing size of waiting lists.
Recent weeks have also seen much debate and concern about the Sláintecare reforms, following the resignation of senior officials.
Mr Reid today reiterated his commitment to the programme, saying Sláintecare was the reason he took up the job as HSE CEO.
He said it's not just a plan for the future, as some of the reform measures are already being implemented across the health service.