Bay of Plenty District Health Board fired a female employee last month for breaching the privacy of 48 patients.
DHB privacy officer Gail Bingham said the termination followed a four month investigation which was initiated by complaints from other staff.
Ms Bingham said the woman had access to patients' electronic medical records as part of her job. She was found to have accessed records for her own personal reasons over a four year period.
Ms Bingham said the patients were known to the woman and in some cases were colleagues and their family members.
She said the patients have been told about the breaches and advised to contact the Privacy Commissioner if they wish to pursue the matter.