A construction site in Melbourne's CBD has closed and 20 colleagues are self-isolating after a worker tested positive for coronavirus.
Multiplex's $2.8 billion Melbourne Square worksite at Southbank was closed on Monday night after the construction worker had the diagnosis.
"Multiplex was notified last night that a worker who attended work at our Melbourne Square site was found to have tested positive for COVID-19," regional managing director Graham Cottam said in a statement on Tuesday.
"We immediately carried out a full clean and sanitisation of the site in accordance with latest protocols."
Mr Cottam said work at the site is expected to resume within 24 hours.
In a statement, the construction union said all workers on the site had been notified.
"Twenty of these workers who were identified as having been in direct contact with the individual are now in self-isolation for the next 14 days," a CFMEU statement said.
The union said the worker immediately began self-isolating after his partner was diagnosed with COVID-19.
The couple is among 917 people who have been diagnosed with the virus in Victoria.
Australian Associated Press