As a result of the incident, the production of plastic cards, including European Health Insurance Cards and medical cards has been paused.
The Health Service Executive says a small number of HSE records were accessed during a cyber attack on the systems of an external card printing service.
As a result of the incident, the production of plastic cards, including European Health Insurance Cards and medical cards has been paused.
The HSE says it was alerted by an external provider of card printing services of a cyber-attack on their systems.
It immediately activated its cyber security protocols, and the HSE ICT systems were not compromised.
However It's understood that a small number of HSE records were accessed.
The production of the plastic cards has been paused as a result, including EHIC cards, GP visiting cards, medical cards and drugs payment scheme cards.
Certificates providing the same entitlement to healthcare while abroad are being issued instead of plastic EHIC cards.
The processing of applications for medical cards and other health service schemes is not affected.
Applicants will receive a letter confirming their eligibility for the relevant scheme, and the HSE says there is no impact on access to healthcare services.

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