There have been 4,181 further cases of Covid-19 confirmed in Ireland today by the National Public Health Emergency Team (NPHET).
The Department of Health says there are now 668 people in hospital, with 125 of those in ICU.
It comes as the CEO of the HSE hailed the "strong turnout" in vaccination centres across the country this weekend for booster jabs.
Paul Reid said: "Our actions to mitigate risk in hospitals, along with boosters and the public response to supporting the public health measures are key to getting us through this tough phase."
Dr Tony Holohan also issued a statement on Sunday warning that the current level of Covid-19 "is having a negative impact on the health of the people of Ireland and placing an enormous burden on our entire health system".
However, the Chief Medical Officer added that "through small but vital individual and collective actions we can turn this around".
"We are all, understandably, very tired of this pandemic. Time and again we have asked the Irish people to take on board public health messaging and act for the collective good," he said.
"And time and again the vast majority have listened to that message and responded.
Over 90% of those eligible have come forward for vaccination and this high-level of vaccination uptake is having a positive effect, especially in preventing severe illness, hospitalisation, and deaths. We know that booster vaccines will add to this protection.
"At high levels of transmission, we are very vulnerable to sudden, unsustainable surges of infection, such as we are seeing at the moment. It is for this reason that we must now ask people to continue to heed public health messages. We know that this call is more difficult to respond to now than at any time previously."
He added: "Most restrictions have been removed and society has largely reopened. We know that, as a result, many people feel unsure about what they should or should not be doing. People can now choose to engage in any number of different activities, across any number of different locations.
"However, this does not mean that every environment available to you is a low-risk setting for COVID-19. It is critically important that everyone is aware of the public health measures you can take to protect yourself and help stop the spread of this disease. The core public health advice to people remains the same."
