Heather McNair chief nurse at York and Scarborough Teaching Hospitals NHS Foundation Trust said that the virus was not going away anytime soon.
There are currently 15 patients in hospital with Covid across the Trust, last month there were none.
Mrs McNair told a meeting of North Yorkshire County Council’s Scarborough and Whitby Area Committee on Friday July 9 that some of those who were in hospital had received both doses of a Covid vaccine.
She said: “A month ago we had no Covid patients in our hospital, today we do have a ward full of patients and one in the ICU.
“The message I would like to share with you all is that some of their patients are double vaccinated. This is a disease that can still affect you and still make you poorly when you are double vaccinated.
“We have got a ward at the moment full of Covid patients in our hospital and that is not going away anytime soon.”
On Monday July 19 the majority of the remaining Covid restrictions will be removed by the Government, including the mandatory wearing of masks.
On Wednesday, Amanda Bloor, NHS North Yorkshire Clinical Commissioning Group’s accountable officer told a meeting of the North Yorkshire Local Resilience Forum that there were 47 Covid patients in the county’s hospitals.
She said that despite the number doubling in a week it was still well below figures seen in January.
Mrs Bloor said: “If we compare previous months, the last time that the infection rates across North Yorkshire and York was at 300 per 100,000 population was in late January of this year and at the same point in time there were over 400 patients in hospital beds in North Yorkshire, so you can see the difference.
“This does give us confidence that the vaccination program is having the anticipated impact around reducing the risk of death and reducing serious illness, especially where those people have received both doses of the vaccine.”