At least 8,500 HSE staff are absent due to Covid-19.
However the Head of the HSE says the true figure could be double that.
It comes as NPHET meet to discuss potentially changing the length of time close contacts have to isolate.
The Government requested public health officials review the isolation rules as businesses and essential services struggle to cope without staff.
HSE Chief Executive Paul Reid admits the official figure is a week old:
"We do know the acceleration we saw in the period of that week, to give examples, some healthcare settings went from 60 people out - staff out, to over 300 people out during the course of this week. So our judgement on it is that we could be at least 12.5% impact on staffing levels and it could be even double the number that we're reporting on today."
