A memory card containing the names, addresses, birthdates and marital status of more than 18,000 people has been stolen from a Peel Region employee’s car.

The information belonged to people who were part of Peel Public Health’s Healthy Babies Healthy Children program between March 2010 and August 2011. Information from 46 people who took part in the program earlier was also stored on the card.

Staff used the kind of data stored on the card to decide how to best serve clients, such as determining who might benefit from a home visit instead of a telephone follow-up, said Dr. Eileen de Villa, Peel’s associate medical officer of health.

A Health Services employee reported the unencrypted SD card missing on Sept. 24. The card is believed to have been in a bag stolen from the employee’s car.

“It is not standard or acceptable practice for any staff to put client information on unencrypted devices,” de Villa said.

Peel Region chair Emil Kolb said the theft occurred despite practices in place to protect clients’ privacy. “I apologize to all residents of Peel — but most importantly to those who were directly affected — for this breach.”

Ontario privacy commissioner Ann Cavoukian said she was disappointed to hear about the lost memory card and “astounded” that such a portable, unencrypted storage device was being used. “I call on all Ontario health care organizations to review their practices immediately.”

The orders stem from other incidents where personal data was lost, including a 2009 case where a Durham Region nurse lost a USB stick containing information on 83,000 people who received the H1N1 flu shot.

The Personal Health Information Protection Act requires information custodians, such as medical officers of health, to make sure information is protected against theft, loss and unauthorized use or disclosure. They are also required under the act to ensure the information is protected against unauthorized copying, modification or disposal.

Clients whose information may have been on the card are being notified by letter and/or telephone. Anyone who was in the Healthy Babies Healthy Children program between March 2010 and August 2011 and is looking for more information can call 905-791-5202 or 1-866-888-9007.

Police continue to help search for the card.