The Chief Medical Officer Dr Tony Holohan has written to the Health Minister Stephen Donnelly this evening expressing concern at the latest Covid-19 figures.

He is urging people to keep their social contacts low and not to hold household gatherings tomorrow night, New Year's Eve.

It comes as 20,554 new cases of Covid-19 were confirmed this evening. There are 619 people being treated in hospital with the virus.

The 14-day incidence of the virus is now estimated at over 2,300 per 100,000 population.

The letter follows a meeting of the State's most senior civil servants this afternoon at which Dr Holohan gave a presentation.

This evening, Minister Donnelly gave updated advice in relation to the Covid-19 community testing and the period of isolation for people diagnosed with the virus.

The minister said that symptomatic people aged 4-39 years should self-isolate immediately and undertake regular antigen tests rather than booking a PCR test. He advises that if Covid-19 is detected in the antigen test, then a confirmatory PCR test should then be sought.

If the virus is not detected in the antigen test, then people should continue to self-isolate until 48 hours after the symptoms have resolved.

Mr Donnelly says that healthcare workers should continue to seek a PCR test and all other symptomatic individuals (people aged 0-3 years and those over 40) should seek a PCR test as soon as they display Covid-19 symptoms.

Anyone who received a booster vaccine and gets Covid will have to isolate for seven days, rather than the current ten days.

The Minister said that antigen tests for people aged 4-39 and who do not have an underlying condition will be provided by home delivery from a central distribution point.

"The HSE has advised that arrangements to provide for distribution of antigen tests can be operationalised from next Monday 3 January 2022," Mr Donnelly said.

"In the meantime, if antigen tests are available to you and you display symptoms of COVID-19, you can use antigen tests as directed as an alternative to PCR testing. As always, if you have any clinical concerns, at any time, please contact your GP."

NPHET is scheduled to meet again next Thursday where a comprehensive review of the recent hospital admissions will be studied.

The early data is suggesting that the majority of patients presenting to hospitals over the last number of days are unvaccinated or partially vaccinated.

Both the CMO and Government are expected to re-emphasise that the booster vaccine can have an impact just three days after it is administered.

Government sources have insisted again this evening that schools will reopen next week and substitute teachers from training colleges will be deployed if needed.