Dubliners have been warned Covid-19 may be on the rise in the capital again, nearly two weeks since Level 3 restrictions were implemented.
The spread of the virus appeared to show signs of stabilising last week, but in recent days the incidence has increased.
Professor Philip Nolan of Maynooth University, who tracks the virus for the Government, said last night: "We need to remain vigilant to ensure we do not lose the ground gained across Dublin since we moved to Level 3.
"We must also ensure we do not see further deterioration outside the capital."
He said he is less optimistic than he was last week and the next few days will be crucial in showing if the rise in Dublin is a slip or part of a pattern.
There were 429 new cases of the virus diagnosed yesterday and 189 of these were in Dublin. There was one further death from the disease reported.
Covid-19 is threatening to spread like a "forest fire" across the country again in a way not seen since the early stage of the pandemic, it emerged last night.
Acting chief medical officer Dr Ronan Glynn warned that time may be running out for people to slow down the spread of the virus and they should act like it was the "end of February" when the country was about to plunge into months of rising infections.Embers
"This is going in the wrong direction. It is becoming a national issue. I would liken it to a forest fire where we are seeing lots of embers," he said.
He appealed to everyone to heed the public advice, not just to individuals but to all sectors and organisations.
"The window for it not to become a national issue is closing - that is why I am appealing to all counties," he said.
There was another rise in the number of hospital admissions announced yesterday, with 130 in hospital and 15 of those cases in intensive care.
There were four deaths from the disease in August and 24 in September.
The average number of new cases a day has risen from 276 last week to 332.
Dublin has three times the incidence of the rest of the country, but most other counties are suffering an increase in infections.
Cork, Galway, Roscommon and Monaghan are among the counties under surveillance for further restrictions, but no county can afford to be complacent.
The National Public Health Emergency Team (Nphet) will meet today to review the worrying spread of the virus.
The possibility of further city lockdowns appeared to recede yesterday, and county-wide restrictions may remain the strategy for trying the curb the virus.
Outside Dublin, there were 60 new cases in Cork, 31 in Donegal, 28 in Galway, 18 in Kildare, 15 in Wicklow, 15 in Clare, 12 in Limerick, nine in Meath, eight in Louth, seven each in Cavan and Longford, six in Laois and five each in Offaly and Westmeath.
The remaining 14 cases were spread across eight other counties.
The R number, the rate at which the infection spreads and which needs to be under 1, is currently at between 1.2 and 1.4.
There has been a sharp rise in cases in 19-24-year-olds.
One of the signals that Level 3 restrictions are not being fully adhered to in Dublin is that the level of traffic on the capital's roads remains high, according to Dr Glynn.
This suggests too many people who have been asked to work from home are going into the workplace and an appeal was made last night to employers to follow the latest health advice.
Reducing the number of people that we meet remains the cornerstone of the collective effort against the virus.
"This evening there are 130 people with Covid-19 in hospital - 15 in the last 24 hours," Dr Glynn said.
"Recently we asked everyone to halve their social contacts. Reducing the number of people that we meet and engaging safely with a small core group remains the cornerstone of our collective effort to reduce the spread of this virus and its impact on our own health and the health of the people that we care about."Threat
Dr Colm Henry, HSE chief clinical officer, said community transmission - where people who are infected do not know where they picked it up - represents the greatest threat to patients and staff in hospitals and residential care facilities.
"When you are making plans to meet friends and socialise this week, take a minute to consider our healthcare workers, who have been at the frontline since the beginning of the pandemic, in hospitals, in nursing homes and in our homes, caring for those who are ill and those who are the most vulnerable to this highly infectious virus," he said.
"Every time you wear a face mask, wash your hands, cover your coughs and keep your distance, your actions are not only preventing the transmission of the virus, but you are also protecting older and vulnerable people and healthcare workers."
Dr Breda Smyth, director of Public Health, HSE West, said: "It is important for everyone to stay connected, but you need to do this in a safe way, at a distance, and virtually as much as you can."