A further 52 coronavirus-related deaths have been announced this evening alongside 866 new cases.
Health officials said 33 of the deaths happened this month, while 12 occurred in January and six occurred in December.
It takes the death toll in Ireland to 3,846 and the national case total to 206,801.
Of the cases announced this evening, 281 were in Dublin, with 63 in Galway, 56 in Kildare, 47 in Meath, 39 in Cork and the remaining 380 spread across all other counties.
This morning, there were 984 COVID-19 patients in Irish hospitals, with 172 in intensive care.
The Deputy Chief Medical Officer Dr Ronan Glynn said NPHET is now “cautiously optimistic” about the situation facing the country.
“This positive momentum has been achieved through the dedication of people across the country in recent weeks,” he said.
“However, incidence and mortality rates are still very high and the significant risk of community transmission of the virus remains, especially for those most vulnerable to COVID-19 infection.
“It is of vital importance that people continue to stay at home and to work from home where at all possible.”
By Monday, a total of 242,353 vaccine dose had been administered - with 154,900 people receiving their first jab and 88,453 people fully vaccinated.
The Chair of the National Immunisation Advisory Committee Professor Karina Butler said the figures were a “wonderful achievement.”
“I want to thank all our vaccine administration teams for their dedication and hard work,” she said.
“We hope that, as our vaccination numbers go up, we can offer more protection to those who are vaccinated and ultimately the wider population.
“Until that time, all of us, including those of us who have received our COVID-19 vaccines, must maintain our adherence to all of the other public health measures, like washing our hands and social distancing.”
The 14-day rate of the virus in Ireland has now dropped to 299.6 cases per 100,000 people.
The five-day moving average is 856 and the seven-day incidence is 129.2.
Monaghan still has the highest rate in the country at 578.3 cases per 100,000.
Nine counties are reporting 14-day rates higher than 300.
The Chair of the Irish Epidemiological Modelling Advisory Group, Professor Philip Nolan said it is essential that people isolate immediately if they have any symptoms.
“In the last week, the HSE has begun to test close contacts of confirmed cases,” he said.
“This is a positive move as it clearly shows that we are back in the containment phase of this pandemic; however, the positivity rates among household contacts is quite high – close to 30%.
“This is a timely reminder to us all to immediately isolate ourselves if we have any symptoms, to protect those most important to us.
“We should also continue to limit our social contacts. Do not visit another person’s household unless you are providing essential care.”
Of the 118,395 tests carried out in the past week, 5.6% came back positive.