Taoiseach Leo Varadkar has announced that the COVID-19 measure could last for several months, in a rare live televised address to the nation.
Varadkar has also said that "this is the calm before the storm" and that the financial damage will be "significant and lasting".
"Our country is making big demands of healthcare staff and every one of us" he said to the country during a state broadcast this evening.
"We're in middle of global and national emergency, a pandemic.
"So far number of cases has been relatively small, however we believe that there will be 15,000 cases before the end of the month, and more from there onwards.
"Vast majority will only expeirence mild ilness, many will be hospitalised and some will die. We can't stop it, but we can slow it and push it back.
"We just don't know when it will be over, the emergency will likely to go beyond March 29th, and could last several months into the summer.
"I know these choices won't be easy, but they're necessary".
The head of state said all resources available would be deployed "to ensure shops and services can stay open" but is asking members of the public for their cooperation in ensuring social distancing guidelines are adhered to.
"That means adjusted working hours, staggering breaks, doing teleconferencing where possible.
"Avoiding unnecessary journeys, ordering online and getting things delivered, instead of physically visiting the shops.
"We're asking people to come together by staying apart from each other."
Varadkar also said that a widespread self-isolation period of several weeks for the elderly and most vulnerable will be put in place, but that the government "will put systems in place to make sure you get supplies and are checked in on, it's called cocooning and it will save many lives.
"Phone neighbours, and make sure those living alone and aren't left alone.
"We have the capacity to borrow millions if we need to. The damage will be significant and lasting, the bill will be enormous and it will take years to pay it.
"This is the calm before the storm, before the surge, and it will come.
"Never will so many ask so much of so few. We will do all we can to support them"
Finally, the Taoiseach urged members of the public to take advice only from trusted news sources, and not to cause undue panic by forwarding viral messages online.
"Please don't forward messages that are from unreliable sources, so much harm has already been caused by those messages, fear is a virus in itself.
Please take breaks from watching the news and media, constantly scrolling on your phone and obsessing isn't helping anyone.
"I want to send a message around the world, we are in this together.
"To everyone who has lost a loved one from this virus, we are with you, for everyone living in the shadow of this virus, we are with you."
The announcement comes following a video-conference between Varadkar and other European heads of state to agree emergency COVID-19 leigslation.
Earlier the Fine Gael leader tweeted that this St Patrick's Day was like "no other" and urged people to help push back the spread of the virus.
Tonight at 9 I’ll speak to you on @RTE and @VirginMedia_One. This is a Patrick’s Day like no other. We cannot stop the virus but we can push it back. We will always put your life and your health first. In future let them say: when things were at their worst, we were at our best
— Leo Varadkar (@LeoVaradkar) March 17, 2020
While, as expected, there was a further rise in cases in Ireland, with 69 announced this St Patrick's Day, bringing the total to 292 in the Republic,
The HSE is also to meet with private hospital operators this week in the hope of using private beds to deal with the coronavirus outbreak.
