Update: Royal Melbourne Hospital is reimaging all of its PCs running Windows XP after it was discovered that the bug that infected its systems on the weekend is a new variant of the Qbot or Qakbot worm, a known piece of malware that exploits a security vulnerability in XP.

A source at Royal Melbourne told Pulse+IT that the malware particularly affected the pathology department, where the majority of PCs run on XP and the laboratory information system runs on Windows Server 2003.