The South West's largest hospital has declared a critical incident after a "tough" festive period.
Bosses at Derriford Hospital have said this winter could be the most challenging it has ever faced as the Omicron variant leads to considerable staff shortages and delays to planned operations.
Chief Operating Officer Jo Beer said: "This morning (January 4) we communicated to our staff that we are operating in an internal critical incident.
"This is due to the high pressure on urgent care services and increasing demand for Covid beds.
"We currently have 99 Covid positive patients across Derriford and our three community hospitals and just under 500 staff absent for Covid-related reasons.
"We don't want people to be alarmed by this. We took the decision to escalate to the highest level of internal incident because this allows us to be able to take additional steps to maintain safe services for our patients and help us cope with the growing pressures.
"Please be assured, we are still here for you, if need us, in an emergency."
Thousands of NHS staff in the South West are off sick - with almost a third of absences due to Covid.
The latest data - which is for December 26 - shows there were almost 6,000 members of NHS staff absent from work through sickness or isolation in the South West, a rise of almost five per cent compared to a week previously.
Around one third of those absences were directly related to Covid-19.
In the week before Christmas, staff absences in the region peaked at 6,500 on December 21 before dipping slightly over the festive break.
Derriford Hospital had the highest number of staff off sick with 772 absences recorded on Boxing Day, 340 of which were because of coronavirus or self-isolation.
The hospital had an average of 850 staff members off work in the week up to December 26. An average of 380 were directly related to Covid.
This is the second time the hospital has declared a critical incident in the past 12 months. In August last year, when 97% of beds were occupied, managers said an increase in Covid admissions and a high demand for the emergency department during the tourist season.
Great Western Hospitals NHS Foundation Trust in Swindon has also declared a critical incident saying it is "extremely busy" as 67 patients are treated for Covid and many members of staff isolate.
People are now being urged to "play their part" in helping the NHS by getting vaccinated and minimising the spread of coronavirus.
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