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 today 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.”