SASKATOON -- Saskatchewan health officials are reaching out to patients who may have been exposed to surgical instruments that were not fully sterilized.

The Saskatchewan Health Authority says the instruments were used on three people at Saskatoon City Hospital on Feb. 1 and Feb. 4.

The authority was unable to identify the three patients, so it has notified 13 people who may have been exposed during surgery on those two days.

The instruments were sterilized through a washer-disinfector cycle, which destroys blood-borne pathogens, including HIV, hepatitis B and hepatitis C.

They did not go through a final step of steam sterilization.

The authority says it is sorry for the mistake but that the risk of infection remains low.