Some hospitals are introducing visitor restrictions to combat a sharp rise in Covid-19 cases.
The State is collecting less data on virus figures, leaving hospitals in the dark about how drastic this wave may be.
The rate of positivity of Covid tests is around 35%.
Professor of Health Systems at the School of Nursing in DCU, Anthony Staines, says that's an alarming figure.
"I think the surge itself is quite significant. We haven't got the detailed figures that we had about the number of cases that we had in the past.
"Looking at countries that do, the UK for example, their number of cases is rising sharply and ours is almost certainly the same.
"We're seeing some of the impact, at the weekend for example there were a substantial number of flights cancelled because staff were not available as they were ill at home with Covid."
