A further 6,735 cases of Covid-19 have been confirmed in the Republic, with some businesses struggling to keep their doors open as soaring infection numbers impact staffing.
Almost half of the latest swabs taken for the virus returned as positive, with a test positivity rate of 49 per cent reported on Monday.
This is up from 39 per cent on St Stephen's Day and 32 per cent on Christmas Day.
Case numbers in excess of 10,000 were recorded for the previous three days - with Monday's dip likely due to reduced testing capacity over the Christmas period - while hospitalisations have also begun to trend upwards.
Hospitalisations rose by 35 Covid-19 patients overnight, bringing the total number in hospital with the disease to 461. Of these, 91 people are in intensive care.
Businesses have reported major staff shortages as the Omicron variant causes a surge in infections, with at least 75,000 people self-isolating around the country after contracting the virus.
This number is potentially four times as high once close contacts are included.
While St Stephen's Day would normally be the start of a post-Christmas spending boom, some shops yesterday reported lower than expected sales as many struggled to continue operating at all due to staff shortages.
Neil McDonnell, head of small business group ISME, said it is becoming increasingly difficult for some companies to keep their doors open.
“It is becoming very difficult to get replacement staff... there are very significant levels of reporting of people who are isolating at the moment, and the current Omicron [variant] does appear to be spreading extremely quickly,” he told Newstalk radio.
“Obviously the service businesses are the worst affected, it’s also particularly acute in areas like childcare where there are specified minimum ratios of staff to children or clients, places like nursing homes.
“So in those settings it is very difficult to maintain a regular level of service when rostered staff fail to show up because they’re self-isolating.”
Ireland is in the grip of an Omicron wave of coronavirus, with most counties in the State recording an infection rate of at least 1,000 cases per 100,000 people.
The capital continues to be the worst-affected area of the country, with one in every 52 people in Co Dublin testing positive for Covid-19 in the latest two weeks.
Post-Christmas demand for PCR tests has been described as “extremely high,” with limited availability for appointments through the HSE’s booking portal on St Stephen’s Day.
Walk-in vaccination centres reopened on Monday after closing during the Christmas period, as officials seek to roll out booster doses in an effort to tackle the Omicron variant.
A further 10,404 confirmed cases of the virus were reported on St Stephen's Day. It followed a record 13,765 cases notified on Christmas Day, up from the 11,182 announced on Christmas Eve.
In the wake of Christmas celebrations, the country’s chief medical officer has urged the public not to meet indoors with anyone outside of their household, and to leave any retail environments not following public health guidelines.