The chief medial officer has urged people to meet only those they plan to spend Christmas Day with in the coming days in a bid to cut social contacts.
Tony Holohan also made a plea to young people to reduce their social contacts as the incidence rate in the young adult population continues to rise.
“I would urge all parents, guardians and extended friends and family to support the young people in your lives to reduce their contacts,” Dr Holohan added.
“I know that this is not an easy task for any of us and it can feel very unfair that we continue to ask so much of our young people, particularly at this special time of year.
“This group have made significant sacrifices in order to protect loved ones and I would like to thank them for that.
“It is important now that we continue to encourage and support each other to make sacrifices, take responsible actions and continue to follow the public health advice.
“This week, try and only meet with the people with whom you will spend Christmas Day. Keep your contacts as low as possible in order to protect those around you.”
Dr Holohan also said that around one in six young people have yet to come forward for vaccination or are not fully vaccinated.
Omicron now accounts for about two thirds of confirmed cases of Covid-19 in Ireland.
Public health teams are reporting a higher level of infection among household close contacts as a result of Omicron infection.Dr Tony Holohan
“Public health teams are reporting a higher level of infection among household close contacts as a result of Omicron infection,” Dr Holohan added.
“If there is one positive test, whether from a PCR or an antigen test, within a group such as a household then there is a significant chance that others are already infected, even if not yet testing positive.
“If one person from a household tests positive prior to an event or gathering, then none should attend.”
The Government issued new advice on Tuesday that people who had the virus should wait three months before getting a booster shot.
Previously, people had to wait six months after contracting the virus before getting a booster jab.
Minister for Health Stephen Donnelly said: “I welcome this update to our booster vaccination programme.
“As with the update to the programme I announced last week, decreasing the interval for booster doses in those who have had a breakthrough infection is an important step given Ireland’s current epidemiological situation.
“The emergence of Omicron has prompted this amendment, specifically the significant concerns we have about the risk of re-infection which is estimated to be approximately five-fold higher with Omicron compared to the Delta strain.
“Christmas week is an important time for many people as we look forward to seeing family and friends and taking a break at the end of a challenging year.
“This year, it is important that we take all the measures we can to break the chains of transmission from Covid-19.
“Each of us can take actions this week to protect ourselves and our loved ones, even if this means rethinking plans for the Christmas period, especially if you are not yet boosted or vaccinated.”
Meanwhile, Taoiseach Micheal Martin thanked the public for their resilience in the ongoing coronavirus pandemic.
Speaking in Government Buildings in Dublin, he told said: “I want to thank the Irish people for their resilience, their capacity to adapt against the biggest challenge from Covid-19… and I really want to thank people for the manner in which they have dealt with this, not just in their behaviour but also getting their booster vaccine.”
Mr Martin said the Irish Government is keeping recently announced new coronavirus restrictions “under constant review”.
“The key criteria is the general health of the population, protecting public health, protecting lives of people,” he said.
“We still need more comprehensive data in respect of the severity of Omicron, the degree to which high numbers of cases will convert into hospital admissions… that is a key consideration and obviously we will be working with other countries, the United Kingdom and others, to get a handle on that data as soon as we possibly can.
“That will inform our approach.
“Suffice to say, this year, because of the fact that we have vaccines, the booster vaccine, that fact we have such a high number of the population with primary doses of the vaccine… so we’re hopeful that the combination of the vaccines with the level of restrictions… that we can get through Omicron.”
Mr Martin said earlier on Tuesday that the Government cannot risk letting the Omicron variant of coronavirus “rip” through the population.
Mr Martin has said that while there are doubts over Omicron’s severity, the experience of last Christmas shows we cannot “let it rip and hope for the best”.
Last January saw one of the most significant waves of the pandemic, with hospitals pushed to breaking point following the arrival of the Alpha variant and increased socialising at Christmas.
Ireland now second in the EU for booster doses administered.— Micheál Martin (@MichealMartinTD) December 20, 2021
Thank you to the vaccination teams, pharmacists and GPs across the country - and the members of the public coming out in such big numbers. https://t.co/8GIXNrCBu4
Mr Martin said about the experience of last year: “It does weigh on me, of course, and there are similarities here.”
He added: “There was a variant arrived on the scene. We didn’t have as much knowledge perhaps of Alpha as we now do of Omicron.
“We know what happened in terms of when a variant comes along that has a significant advantage over the previous iteration of the virus.
“It can wreak havoc and you get many, many new cases, you get more hospitalisation.”