People are being "strongly discouraged" from attending Christmas parties as Omicron cases rise.
Urgent steps are needed to protect hospital staff and patients as pressure on the NHS increases, Cardiff and Vale health board has warned.
The health board posted a stark warning on Twitter asking people to stay away from Christmas parties and follow coronavirus guidance.
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The statement read: "In light of Omicron and increasing pressures we need to take urgent steps to protect ourselves, our colleagues, and our patients.
"We strongly discourage attending Christmas parties. Please continue to stay safe and follow national guidance."
The most recent data published by Public Health Wales on Friday, December 10 confirmed a further four cases of the Omicron variant in Wales, bringing the total number of cases to 13.
Dr Meng Khaw, national director for health protection and screenings, said two of the new cases were in the Cardiff and Vale health board area, one of the cases was in the Swansea Bay health board area, and the other case was in the Hywel Dda University Health Board area.
A statement on Friday said: “Public Health Wales is today (Friday 10 December) confirming two new cases of Omicron variant in the Cardiff and Vale University Health Board area, one new case in the Swansea Bay University Health Board area and one new case in the Hywel Dda University Health Board area. This brings us to a total of thirteen cases in Wales, of which four are linked to international travel.
“As we have said previously, an increase in cases of Omicron variant in Wales is to be expected.”
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