A further six people have died in the Republic after being diagnosed with COVID-19, the NPHET has confirmed.
Twenty-three more people have also tested positive for the disease, bringing the total number of cases to 25,437.
Of those 23 new cases, ten are in younger adults under 35 years old, and eight are aged between 35 and 54.
No new cases were reported in Galway, so the total number of positive test results in the county remains 485.
Dr Tony Holohan said that there have been high levels of compliance with public health advice, and this has allowed for the further deescalation of measures brought in to tackle COVID-19.
But the Chief Medical Officer said that the age range of the new cases is “a real concern and a worrying trend” at a time when many people are reconnecting with friends and loved ones and may be gathering in larger groups.
“In recent days, for example, some cases have had large numbers of close contacts that have required testing and self-isolation for 14 days.
“COVID-19 is an infection that affects all ages and it is incumbent on all of us to take our individual responsibility seriously,” he said.
Dr Holohan emphasised the importance of keeping informed, keeping a two metre distance from others, following the public health advice on hand washing, and wearing face coverings.