Acting Chief Medical Officer, Dr Ronan Glynn, has not ruled out introducing Level Three lockdown restrictions on Cork city while leaving county areas at Level Two.
Dr Glynn has raised the prospect of Cork becoming the first county operating at two different levels of coronavirus restrictions.
He said split restriction levels could happen, as NPHET "continues to evolve its approach" to assessing local areas.
The rate of Covid-19 in Cork is "rising fast" with one in five cases now linked to pubs and restaurants.
The county recorded a further 27 cases yesterday, bringing to 364 the total in Cork over the last fortnight. The Acting CMO says the National Public Health Emergency Team (NPHET) is now "very worried".
He confirmed 70 of those cases are linked to pubs and restaurants.
He says he is not focused on moving Cork to Level Three restrictions, similar to Donegal and Dublin, but government sources have cautioned that the county could be up for consideration as early as Friday.
Michael O'Donovan, a publican in Cork city and chairman of the local branch of the Vintners Federation of Ireland, said it is disappointing to hear that 70 cases are linked to pubs and restaurants and he expressed concerns that pubs will once again be forced to close.
He highlighted that 'wet pubs' are only open since last Monday and many of the 70 cases could be linked to establishments serving food.
"We're asking people to please be vigilant and to follow the guidelines because if we don't, we don't want to be returning to a situation like in Dublin and Donegal where the bars could end up closing again," he said.
Dr Glynn reminded the people of Cork that there is more work to be done to stop the spread of the virus.
"I don't speculate on the need for additional measures. If additional measures are needed, that will be a recommendation made by NPHET on Thursday.
"The reason we highlight counties is that people can take a bit of additional action to try to avoid a situation where additional measures aren't required."
Dr Glynn said there has been a relaxation of distancing, saying that it was the "single biggest thing that people can do".
"There are no new messages - but one, in particular, is that people need to keep their distance."
Last night's HSE's briefing also heard from Jerick Martin, a healthcare worker who spent 68 days in an Intensive Care Unit after contracting Covid-19.
"I was a fit and healthy man in my thirties, working and enjoying my life with my wife and my daughter.
"I caught Covid-19 and within five days of experiencing my first symptoms, I was admitted to hospital, where I spent 68 days in intensive care, most of that time on a ventilator, in an induced coma.
"I was told by my doctor that I would be in the induced coma for a few days, but I actually woke up two months later.
"I am asking now for everyone to be careful."
Dr Glynn said that Jerick's case highlighted that the effects of the virus are unknown and that the virus was not "just bad flu".
He said that of the 27 people who have died of the virus in September, seven were under 65 and seven had no underlying issues.
Meanwhile, Taoiseach Micheál Martin appealed for "extra focus" over the coming weeks, urging young people to listen to the personal experiences of those who have contracted Covid-19.
Mr Martin made his comments after a Cork student tweeted that he had been rushed to hospital and temporarily paralysed after testing positive two weeks ago.
Ben Quigley tweeted from Rennes in France on Sunday that he had been brought to hospital via ambulance as he was unable to breathe.
“I was convinced I was on my deathbed. I’m 20 years old. Stuff like that isn’t supposed to happen to a 20-year-old,” he tweeted.
An additional 390 cases of Covid-19 were reported last night, with 209 of these cases in Dublin.
There has now been a total of 35,377 confirmed cases in Ireland.