Even in this era of over-sharing and supposed transparency, most people don’t want their medical files shared with anyone who doesn’t absolutely need to see them. But all it takes is one person to not pay attention when stuffing envelopes for private medical documents to be shared with the world.

Last week, a woman in California received the results of her 11-year-old daughter’s blood tests from the UC Davis hospital. But her daughter’s results were not the only thing in the envelope.

“As I started going through it, I says, ‘wait a minute, I don’t know these people,’ ” she told CBS Sacramento’s Maria Medina.

She found lab results for a total of 11 patients, including her daughter.

“They’ve got their address, their names — all kinds of very personal private information, whether the tests come out positive or negative,” says the mom, who says she tried contacting the hospital but couldn’t get through to the specialist that all the patients had been to see: “They told me she doesn’t take calls.”

After CBS Sacramento got involved, the hospital got slightly more responsive, releasing the following statement:

“We sincerely apologize for the breach of patient confidentiality that has occurred. UC Davis Health System has robust safeguards in place to assure the privacy of all of its patients. If a breach occurs, the health system has rigorous processes in place to respond and address them. Any patient whose privacy has been compromised is immediately contacted and informed of the incident. Consistent with this policy, all patients involved in this matter were contacted by telephone today. In accordance with state and federal mandates uc davis health system will report the incident to the appropriate agencies.”

CBS contacted one mother whose child’s test results were leaked. She said that the hospital did contact her, but only to ask if the results had been received. She said there was no mention of her child’s private information being accidentally sent to a complete stranger.

“I’m sure if they didn’t tell me, they didn’t tell the other parents,” she says.

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