Naas General Hospital is "back to where it was in April" as it tackles a large outbreak of COVID-19, the head of the HSE has said.
All elective surgeries and outpatient appointments at the hospital are suspended for two weeks - and 77 staff are off work as they're either a confirmed case or a close contact.
Meanwhile, Letterkenny University Hospital has 55 staff unavailable, and there are 161 off between University Hospital Limerick and Ennis Hospital.
HSE chief executive Paul Reid said outbreaks are putting pressure on the hospitals impacted.
He said: "It is significant in terms of staff impact - both in terms of some positive cases, and also close contacts... and indeed some patients as well.
"We are losing a lot of staff on shifts, and it's causing significant disruption.
"In one case, we've had to cease all elective care - they are now back where they are in April of just doing urgent care. That's in Naas."
Mr Reid said the hospital is currently just dealing with critical and urgent care.
He said the healthcare system is 'at high risk' as long as coronavirus in the community, and the situation can change very quickly.
Figures released yesterday show there were 37 'open' COVID-19 clusters associated with hospitals on Saturday, including 11 new outbreaks last week.