Victorian Health Minister Martin Foley said the outbreak link was "a very serious matter".
"We are determined to get on top of it and I know that requires what appears to some people to be tough measures, but the virus does not respect state borders," Mr Foley said.
"The virus does not respect holiday periods and the virus does not respect many things and we need to make sure that we stay ahead of this cluster and we take all the necessary measures we can to make sure that we bring it under control as soon as possible."
The state also recorded two international cases yesterday, who are both in hotel quarantine. One is an air crew member and the other a returned traveller.