There have been 938 further confirmed cases of COVID-19 and 13 additional deaths related to the virus in Ireland.
There has now been a total of 2,184 COVID-19 related deaths and 82,155 confirmed cases here.
This includes the denotification of 11 confirmed cases.
Of the cases notified today:
- 416 are men / 517 are women
- 65% are under 45 years of age
- The median age is 36 years old
Some 300 cases are in Dublin, 110 in Cork, 72 in Limerick, 68 in Donegal and 41 in Kildare.
The remaining 347 cases are spread across 21 other counties.
As of 2.00pm 251 COVID-19 patients are hospitalised - of which 25 are in ICU.
There have been 24 additional hospitalisations in the past 24 hours.
Chief Medical Officer Dr Tony Holohan said: "NPHET met today and reviewed the current epidemiological situation and has made recommendations to Government.
"Every indicator of the disease is rising and rising rapidly. Our level of concern continues to escalate.
"We must do all we can individually and collectively to change the course of this disease."
He added: "Revise your Christmas plans to ensure social contacts are limited and that hand hygiene, physical distance, ventilation and face covering measures are in place if you must have visitors to your home."
Dr Ronan Glynn, Deputy Chief Medical Officer, said: "The epidemiological situation reviewed today is the most serious it has been since last March.
"People should act at all times as if they or those they come into contact with are infectious.
"The disease has spread across all parts of the country and all age groups, we must act now to protect each other."
"It is inevitable that people will get sick and die as a result of this escalation, but it is not too late for all of us to do all we can to minimise that impact and to protect as many people as possible."
And Professor Philip Nolan, Chair of the NPHET Irish Epidemiological Modelling Advisory Group, added: "The situation has deteriorated further, even in the last two days.
"The reproduction number is higher than we have reported since March at 1.5 to 1.8.
"The day on day growth rate is estimated at 7% to 9%.
"These data emphasise the need for us to be exceptionally careful over Christmas and to adhere strictly to public health guidance."