Pressure on hospitals and GP services is expected to increase next week as incidents of flu are on the rise and expected to peak after the Christmas break.
The Department of Education and the Employers group IBEC say that those with flu symptoms should stay at home to reduce its spread.
Every year between 80 and a 120 people die directly from influenza in Ireland.
However, the Health Service Executive said indications are that this year might not reach last year's peak.
The Irish Nurses and Midwives Organisation, meanwhile, has recorded a total of 2,408 patients on trolleys at hospitals around the country in the first week of 2018.
The figure marks an increase of 221, or 10%, on the same period last year.
It comes as Minister for Health Simon Harris said he accepts the need for more consultants in emergency medicine to be appointed.
However, he said that in the short-term, over the coming days and weeks, all resources needed should be directed at dealing with overcrowding.
Mr Harris also said that the public sector pay commission would be looking at the recruitment and retention of consultants.
The Irish Association of Emergency Medicine (IAEM) has said that Ireland does not have enough consultants to provide extended cover after around 8pm at night in emergency departments.
IAEM President Dr Emily O'Connor told RTÉ News that the overcrowding crisis was fixable.
She said there were international models that work better than what Ireland had and she pointed to Australia and New Zealand as examples.
Dr O'Connor said that Australia had put the proper staffing and resources into its emergency departments.
Earlier, there were two children on trolleys in Dublin hospitals, with one of them having waited more than nine hours at Temple Street.
Yesterday, there were 12 cases of child patients on trolleys.
There are 483 patients are waiting for a hospital bed across the country, down from the peak figure of 677 on Wednesday morning.
Overcrowding tends to reduce as the weekend arrives and rises again at the start of each working week, peaking usually during the middle of the week.
The worst affected hospitals are:
- University Hospital Limerick with 43 patients waiting
- St Luke's Hospital, Kilkenny - 34
- Midland Regional Hospital, Mullingar - 33
- St Vincent's University Hospital - 29
- University Hospital Waterford - 29
- Tallaght Hospital - 28
Last night, Minister Harris phoned hospitals and spoke to managers in Kilkenny, Cork, Tallaght and Galway.
He also made a private visit to St Vincent's University Hospital in Dublin, where during the day there were 21 patients on trolleys. He thanked staff for their efforts during the crisis.
The chief executives of hospital groups will be spoken to again today to keep up to pressure to minimise overcrowding.