At the 1978 Commonwealth Games held in Edmonton, Alberta, Quirk won three gold medals in the 100-metre butterfly, 4x100-metre freestyle relay, and the 4x100-metre medley relay, a silver medal in the 200-metre butterfly, and a bronze medal in the 100-metre freestyle. Later that same year, she won bronze medals for her performances in the 100-metre butterfly and 4x100-metre freestyle relay in the 1978 World Aquatics Championships. In her final international appearance at the 1979 Pan American Games in San Juan, Puerto Rico, she won a pair of silver medals as a member of the Canadian relay teams in the 4x100-metre freestyle and 4x100-metre medley events, together with two bronze medals in individual events, the 100-metre butterfly and 400-metre freestyle.