The Information Commissioner’s Office (ICO) has launched an investigation as up to 13,000 letters – asking the most at-risk groups to stay at home for 12-weeks during the coronavirus pandemic – were sent to the wrong addresses.
The mistake has since been rectified and the Welsh Government blamed a data processing error by the NHS Wales Informatics Service.
Opposition AMs called the breach “potentially disastrous” and “unacceptable”.
The ICO said: “People have a right to expect their personal information to be protected. We’ll bear in mind the current crisis when assessing breach reports such as this, taking an appropriately proportionate approach.”