NPHET is examining if restrictions on Dublin need to go beyond level three.
The situation in Dublin is seen as particularly serious and three weeks of higher restrictions are set to come into effect by the weekend.
This morning the government extended the regulations underpinning the current rules until October 5th.
The government won't make a decision on the public health advice until tomorrow.
Tomas Ryan, immunology professor at Trinity College Dublin, says the country's in a difficult situation.