It was hit with an attack in May.
The National Cyber Security Council warned in October last year that hospitals and the HSE could be the target of hackers.
The organisation's acting director has been speaking for the first time about the response to the cyber attack on the health service in May.
Richard Browne says protocols to deal with the incident were put in place quickly and international experts brought in:
The redeployment of staff within the HSE to deal with the vaccination programme, may have contributed to the increase risk of a cyber attack.
Richard Browne says there was an awareness that hospitals and the HSE could be targeted during the pandemic