Thousands of patients face cancelled appointments and delays to health services next week as the HSE tries to rebuild its IT systems following a cyber attack.
Health Minister Stephen Donnelly said appointments would be cancelled in the coming days due to the attack, but the impact will vary across the country.
A ransomware attack closed down IT services on Friday.
Mr Donnelly said: “The HSE and our cybersecurity team continue to work through the IT systems over the weekend.
“Impacts across the country will vary as some hospitals have data on patients locally.
“However there will be cancellations in the coming days. Patients will be contacted.”
The National Cyber Security Centre (NCSC) has been working with the HSE to identify the affected systems and to bring all systems back online.
The attack affected all of the health service’s national and local systems.
Taoiseach Micheal Martin said on Friday Ireland will not pay any ransom and that officials were dealing with the matter “methodically”.
Systems for GP and close-contact Covid-19 test referrals were among the services affected.
The online system for making child protection referrals to the child and family agency, Tusla, was also down.
The online booking portal for Covid-19 vaccinations, which was suspended on Friday, was back up and running on Saturday.
Anyone between the ages of 50 and 69 can register to receive their jab.
The HSE’s Covid test results and contact tracing services have also been restored to normal.
But GPs are not able to refer patients for a coronavirus test so anyone with any symptoms of the virus is asked to attend a walk-in Covid-19 testing centre.
The country’s vaccination programme has not been affected and will continue as planned next week.
Communications Minister Eamon Ryan and Junior Minister Ossian Smyth held a briefing update with the NCSC on Saturday.
In a statement the department said the NCSC’s “full resources” have been committed to supporting the HSE in its response to the cyber attack, and the NCSC is liaising with international partners and third-party contractors.
“This work will continue throughout the weekend with the focus on supporting the HSE’s recovery process in order to minimise disruption to services,” it said.
Cancer services have been particularly affected, with many non-urgent radiation appointments cancelled.
All outpatient appointments and all non-emergency radiation treatment due to take place on Monday across St Luke’s radiation oncology network sites have been cancelled.
These include appointments at St Luke’s Hospital in Rathgar, St Luke’s Centre at Beaumont Hospital and St Luke’s Centre at St James’s Hospital, in Dublin.
All radiology appointments at Beaumont on Monday have been cancelled. The hospital said patients will be contacted with a new appointment date.
Naas General Hospital in County Kildare said it has cancelled some outpatient appointments scheduled for Monday and that it would be in contact with any patients affected.
All outpatient appointments at St Luke’s General Hospital Carlow/Kilkenny due to take place on Monday have been cancelled, with the exception of antenatal appointments. Routine X-ray, physio and cardiac diagnostic appointments have also been cancelled.
All outpatient appointments at the Rotunda maternity hospital in Dublin have been cancelled for Monday and Tuesday unless a patient is 36 weeks pregnant or later.
Gynaecology clinics and appointments have also been affected.
Children’s Health Ireland at Crumlin Hospital in Dublin said it has cancelled its scheduled inpatient and outpatient services on Monday and Tuesday.
Clinically urgent inpatient and day care treatments (such as cancer, haematology, dialysis, cardiac) are not affected.
Meanwhile, the Department of Health has advised that there will be no reporting of the daily Covid-19 figures on Saturday due to the disruption.
In a tweet it said: “Due to the current disruption of the HSE IT systems daily #Covid19 figures are not available. Backdated figures will be published when possible.”