Health Services CEO Vicki Kaminski says the staff member at Alberta Children's Hospital looked at files belonging to children, adults, physicians, nurses and high-profile people in the community.
Kaminski says the employee had no reason to look at the files and there's no indication the person did anything with them.
The employee was fired.
Kaminski says the affected individuals have been contacted.
The breaches occurred over a 14-month period and were detected during a regular audit of Alberta Health Services patient databases.
The files were not restricted to the children's hospital as the employee, whom Kaminski described as a "lower-level" secretary or clerk, had access to other health data bases in the province, Kaminski said Tuesday.
"We asked the question about why they were accessing it and the information that they gave us was very nondescript, so we don't know," she said.
"We know that it was inappropriate for them to access. We know that they were not part of the circle of care. There was no reason for them to get information on the 240 patients they were looking at. They didn't have to pass that on to anybody.
"We have no idea what they were going to do with it."
There's been nothing to suggest the personal data was made public in any way, Kaminski said.
"Nothing has suggested that there was inappropriate use of the information, but there was inappropriate looking at the information."
Kaminski said Alberta Health Services is constantly working to improve the security of its electronic health records.
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