She warned that hospitals will struggle to cope with an increase in cases, with 1,308 people currently in hospital with the virus, 49 of whom are in ICU.
Ní Sheaghdha highlighted that 570 patients are currently on trolleys in Irish hospitals, a number she called "extraordinary."
"We are managing, but we are getting to a point where it is unsafe care and nobody can stand over that," she said. "We cannot continue with elective care because we don't have enough room in our hospitals and the practice of nursing people with Covid with an airborne infectious disease with those who don't, is very, very dangerous. We saw the hospital acquired infection from Covid increase significantly over the past number of weeks. So our hospitals are becoming reservoirs for Covid and of itself being admitted to hospital now is a danger."
Ní Sheaghdha raised the unresolved issue of poor ventilation in hospitals.
On Sunday Tánaiste Leo Varadkar suggested pandemic regulations would not be reintroduced. He described the pandemic as an "ongoing cause for concern, but not a cause for panic."
"It is a very different situation at the moment," he said. "About half of those in hospital with Covid would be in hospital anyway, it's incidental finding in their cases. This is another wave but we don't anticipate it will necessitate the reimposition of restrictions, but other things need to continue. We need to make sure that people have those boosters and third doses."
