The infirmary used by the students, as well as the Sisters, was located on the third floor of the 1886 wing, on the south side of the building. Like the infirmary on the second floor, this room had a small door, opening out over the choir loft, so that the girls recovering from illness could hear the events taking place in the chapel. It was part of the mission of the Sisters of Saint Ann to heal the sick, and often, the Sisters had training as nurses. They had a reputation for taking very good care of their patients, but once someone was diagnosed, they were sent to bed, and were not to get up until they were well. This strictly enforced rule made pretending to be ill far less attractive for the pupils.
Like the other rooms at the Academy, the infirmary was plain, clean and practical. In addition to the beds, little storage cupboards for supplies and tables for trays and books made up the furnishings. The bed linens were white and sometimes a patchwork quilt was folded over the end. The crucifix, a symbol of the Christian religion, was given a place of honour.
Part of the purpose of this room was to provide a quiet place, where the elderly and the sick could have some rest and peace. It was also intended to keep sickness from spreading through the school, but this did not always work. One boarding student awoke to hear her roommate screaming hysterically. Looking into a mirror, she saw the tiny red bumps of the measles. The nurses took her to the infirmary right away. She lay quietly, and was able to listen to the sounds of the organ and the choir, drifting in from the chapel, until her friends heard of her illness. From that moment on, she recalls, there was a steady stream of girls, stealthily attempting to say hello and entertain her, while the nursing Sisters were occupied somewhere else.
When this infirmary and the one on the second floor could no longer accommodate the older Sisters needing care, Mount Saint Angela and later St. Ann's Residence were set up in Victoria to care for these Sisters.