“Unfortunately we have had to delay some surgery and some outpatient work.” Many health workers have been forced into isolation as parents or close contacts of students at Brisbane Grammar School, Brisbane Girls Grammar and Ironside state school. Venues at the Royal Brisbane and Women’s hospital, the Princess Alexandra hospital and the University of Queensland have been listed as high-risk exposure sites. Young said she was still concerned about the missing cases linking infections in two returned overseas travellers to an Indooroopilly state high school student and her family. “We don’t know how this outbreak has happened.” Nine of the new Covid cases are school students, Queensland’s health minister, Yvette D’Ath, said.