More than 2,700 NI healthcare workers are isolating as a result of Covid-19.
The figures, from the six health trusts, are a significant increase from a fortnight ago when BBC News NI reported that 1,200 staff were isolating across all the trusts.
As pressure on hospitals continued to mount, the Western Trust confirmed that a small number of "red flag" cancer surgeries had been postponed.
The operations were due to take place on Monday and Tuesday.
It is now hoped they will take place on Wednesday, although the trust said that the situation was "fluid".
There have been three more Covid-19 related deaths reported by the Department of Health, bringing the total death toll to 624.
There have also been 913 further positive cases, bringing the total number of cases to 28,953.
In the Republic, Tuesday saw 13 additional deaths related to Covid-19, which was the highest daily figure since May.
It brings the total number of deaths in the country to 1,865.
As of midnight on Monday, the Irish Department of Health reported 1,269 new cases of Covid-19, bringing the total number of confirmed cases to 52,256.
'Lessen the load'
Across the six health trusts, there are 2,747 staff isolating as of Tuesday.
That includes 137 NI Ambulance Service staff who have had to self-isolate.
The Belfast Health and Social Care Trust has confirmed that 1,108 of its staff are isolating for reasons associated with Covid-19.
A total of 393 are symptomatic and a further 375 have been contact traced, the trust said.
"Any increase in staff absence has the potential to impact on service delivery and we will continue to monitor this," the trust said in a statement.
"Where there is an absence as a result of self-isolation and, where possible and depending on their role, the trust has been facilitating staff working from home.
"Symptomatic staff or family members they live with can book a test at our Knockbracken site through a central booking number."
The Southern Trust, which operates Craigavon Area Hospital and is the smallest of the trusts in Northern Ireland, has 505 staff on leave as a result of the virus.
This includes 207 who are symptomatic, 68 who have a symptomatic family member and 165 who are isolating as a result of contact tracing.
In a statement, a spokesman said: "At this stage of the pandemic, when Covid-19 is surging so rapidly in Northern Ireland, the trust is managing high numbers of Covid-19 cases and clusters on several sites.
"We continue to follow national guidance in managing these incidents and we report and manage identified clusters in line with the guidance."
The South Eastern Trust has recorded 157 staff isolating.
The Western Trust has 624 staff in isolation, which includes 198 people who can work from home.
The Northern Trust has 198 staff unable to report to their usual workplace for coronavirus related reasons.
Ulster Hospital nurse Aron Sturdy said he believed measures being put in place would help alleviate some of the pressures but he added that the public also had a part to play.
"We don't know what we are facing in terms of our workload because our staff and team numbers change from one day to the next and can be quite dramatic.
"It's all boiling down to sickness, stress - everything else is just weighing down on the staff and they can't be blamed for it."
He added: "The Downe (Hospital) re-opening will hopefully take some weight of the shoulders of the Ulster Hospital.
"It's about asking the general public engage with all the services; with their GPs and with everything that's being made available to them and to try and lessen that load that's hitting the emergency departments."
'Very worrying time'
In Londonderry, a GP has said the Covid centre at Altnagelvin Hospital has been "like a war zone".
Dr Paul Molloy said the facility was seeing almost as many patients in a day now as it did in a week during the months of March and April.
Dr Molloy said the Covid centre is coping but warned it was vital people adhered to the public health guidance.
More than 20 patients were being treated at the unit on Monday evening, he said.
The Western Trust said that it had activated the "level red" stage of its Covid surge plan and that it was a "very worrying time", with the number of patients needing admission doubling "every three to four days".
"If the rate of infection continues locally, we will have some very difficult decisions to make in the coming days around what services we can continue to offer," it said.
The Western Trust said there are currently 72 patients in the hospital with coronavirus and that it had moved into a "further ward to facilitate increased Covid-19 admissions" on Monday.
The Derry City and Strabane District remains Northern Ireland's highest infection rate, with 770 cases per 100,000 people, according to the Department of Health.