The Chief Medical Officer is "increasingly concerned" at the trends surrounding Covid-19.
Dr Tony Holohan has said the five-day average of daily cases has increased from 350 last week - to 424 today, and has urged people to follow the health advice.
366 new cases of the virus were reported yesterday - as well as 11 deaths, all of which happened in November.
The government's likely to make a decision on how to exit level 5 restrictions towards the end of next week.
Professor of Public Health at UCC, Ivan Perry, believes any plan should involve limiting arrivals from abroad this Christmas.
"During the summer there were cases that we heard about, one individual who travelled back to Ireland from Spain I think it was, went for a few drinks with friends and socialised over the weekend.
"I think there were 87 cases from that one individual, and each of those 87 cases would have further cases.
"It just takes a small number of people who are careless."
