The Deputy Chief Medical Officer says Monaghan is one of four counties with a particularly high incidence of Covid-19.
It comes as nurses warn that overcrowding at hospitals is at its worst since the pandemic began.
Just three per cent of new Covid-19 cases are in people aged over 65.
NPHET says the spread remains highest in the 16 -34 age group.
In a video on social media, Deputy CMO Dr Ronan Glynn said there is concern about the increase in infections locally.
In the seven days up to last Friday, 969 people attended the walk-in testing centre in Cloghan.
Meanwhile, nurses say they are becoming increasingly unsafe in overcrowded hospitals.
The INMO says that with 381 patients are waiting for a trolley, hospital overcrowding is at its worst since March 2020.
116 are at hospitals serving the local region.
University Hospital Galway is the worst locally with 39 patients on trolleys, there are 26 waiting in Sligo University Hospital.
Portiuncula Hospital has 14 patients either in the emergency department or other wards.
There are 13 in Tullamore and 8 in Mullingar Hospital.
Cavan General has nine patients on trolleys and Our Lady of Lourdes Drogheda has 7.
Our Ladies Hospital Navan is one of eight hospitals in the country to not have anyone on trolleys or wards.
