Dr Ronan Glynn has urged every family to sit down and make a plan to reduce the number of people they're going to see this week.
The top doc's warning comes after 430 new cases of COVID-19 were announced today, including 212 in Dublin.
Today's number was the highest confirmed since April 26.
No deaths were recorded in the last 24 hours according to the latest HSPC update.
The Acting CMO is urging people in locked-down-Dublin and Donegal in particular to take heed of the advice.
"As we start into this new week, I am asking every household across the country to sit together this evening and make a plan to reduce the number of people you meet this week," Dr Glynn said.
“We have absolutely no room for complacency.
"If every person, family, workplace and organisation does not play their part the situation will continue to deteriorate.
“For people who live in Donegal and Dublin remember Government advice is to work from home unless it is essential to attend in person.
"For people living in these and all other counties, assume that COVID-19 is circulating in your community and act accordingly."
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