Alberta Health Services said they are contacting dozens of patients who may have been exposed to infection at the fertility clinic at the Royal Alexandra Hospital in mid-November.

On Thursday, Alberta Health Services said they had started to notify the 141 patients of the Regional Fertility and Women’s Endocrine Clinic at the Royal Alexandra Hospital.

AHS the patients had an endovaginal ultrasound at the clinic between November 14 and 20 – and they could be at “exceedingly low risk of exposure” to blood-borne and sexually transmitted infections.

Officials said they first became aware of the issue November 20, and started a review and investigation right away.

AHS said they confirmed the main cause of the issue was human error. Officials said AHS standards for Medical Device Reprocessing (MDR) were not adhered to, including inconsistent tracking and recording of the number of reprocessed probes between the two dates, and overscheduling of procedures.

Patients are being notified, AHS said, as officials can’t be certain all MDR practices at the clinic between those dates were conducted, including tracking and recording reprocessed probes, and proper cleaning and disinfection of the probes used.

While officials are contacting affected patients, AHS has concluded the “risk of transmission of any significant infectious agent is near zero.” AHS said those who wish to be tested will be given instructions for blood and/or urine testing to rule out infection.