People in Donegal should "double down" in their efforts to prevent the spread of Covid-19, the HSE's chief clinical officer has said.
Dr Colm Henry said the county "remains a concern" for public health officials and was an outlier in the State, with case numbers not falling as rapidly as elsewhere.
The 14-day incidence rate in Donegal is at 300 cases per 100,000 people, more than twice the national average.
HSE chief executive Paul Reid said an outbreak of Covid-19 at Letterkenny University Hospital was having a "very significant" impact on staffing.
The hospital has 55 staff unavailable because they are a confirmed case or close contact of someone with Covid-19.
Mr Reid said Naas General Hospital in Co Kildare was "back to where it was in April" as it tackled a large outbreak of Covid-19. All elective surgeries and outpatient appointments at the hospital have been suspended for two weeks.
An outbreak at University Hospital Limerick and Ennis Hospital has caused similar staffing issues and a cancellation of some elective procedures.
Dr Henry said overall transmission of the disease had reduced since Level 5 restrictions were introduced.
"A few weeks ago we were talking of a growth rate per day of 4 to 6 per cent. Now we see negative growth rates of up to 6 per cent, which is very encouraging," he said.
"We're certainly on track for reaching cases of between 50 and 100 per day by the beginning of December, but that depends on everybody continuing to play their part".
Dr Henry said the situation in the UK and the rest of Europe was of "serious concern", with only six countries deemed by the European Centre for Disease Control and Prevention to be "anywhere stable".
