The Department of Health has been notified of 17,656 additional cases of Covid-19.
There are now 928 people in hospital with the virus, up 44 on yesterday's figures.
The number of patients in ICU has risen by four to 94 since yesterday.
In Northern Ireland, 7,133 new cases of the virus and three more deaths have been confirmed.
There has been a total of 5,952 deaths related to Covid-19 notified in Ireland. This includes 40 deaths newly notified in the past week.
There have been 11 Covid-19 deaths in the week 29 December to 4 January, where the date of death was in that week, according to the Health Protection Surveillance Centre.
Dr Tony Holohan, Chief Medical Officer, said: "It is concerning to see the rising number of people with Covid-19 in hospital.
"This means that our collective efforts to follow the public health advice remain very important."
He added: "I know that many have sacrificed valuable time with friends and family to protect themselves and the wider community. These continued efforts are helping to slow the spread of this virus and will protect many from infection in the next few weeks.
"The Covid-19 vaccine booster will protect the majority of people from severe disease.
"The booster programme is now open to everyone aged 16 and over. If you are not yet fully vaccinated or are yet to receive a booster dose, please take this opportunity to protect yourself as soon as possible."
Dr Holohan also urged people to "isolate immediately if symptomatic, keep your social contacts as low as possible, avoid high risk activities and poorly ventilated environments".
Meanwhile a new report shows that 697 patients have been admitted to intensive care units here so far during the fourth wave of Covid-19.
The fourth wave has seen the second highest number of ICU admissions of any of the pandemic waves to date.
It compares with 972 admissions to ICU under the third wave, 170 admissions under the second wave and 436 during the first wave.
There have been more admissions among pregnant women in the fourth wave, than in any of the other three waves.
So far under the fourth wave, 25 pregnant women were admitted to ICU, most in their third trimester.
It compares with one admission of a pregnant woman in the first wave, none in the second wave and 19 in wave three.
The report shows that 22 of the 25 women were not vaccinated.
Of the 25 pregnant women admitted to ICU since late June last year, 12 had underlying medical conditions and 11 needed mechanical ventilation.
The report is from the Health Protection Surveillance Centre.
Of the 697 patients admitted to ICU during the fourth wave, 93 are still in ICU.
The fourth wave covers the period 27 June 2021, to 25 December last.
The median age of admission was 59 years.
In all, 55% of the ICU admissions were discharged alive, while over 31% died.
The report shows that over 79% of those in ICU had an underlying condition.
The most common underlying conditions were hypertension (46%), chronic heart disease (35%) and chronic respiratory disease (29.5%).
The average length of stay for those discharged from ICU was eight days, but ranged from one to 90 days.
The average length of stay for those who died was 11 days but ranged from one to 62 days.
The main area of residence for cases admitted to ICU in the fourth wave was East (36.6%%) North East (12.6%) and South (9.6%).
Meanwhile, Anne Rabbitte, the Minister of State for Disability in the Department of Health and Department of Children, Equality, Disability, Integration and Youth, has said the Department of Health has been informed by the HSE that a decision has been taken today that all appointments [for child vaccination appointments] will be given based on date of registration.
She said that it is expected that all children in Phase One will have an appointment by close of business today.
