The coronavirus has surfaced at a Victorian hospital that treats some of the country’s sickest children.

Five healthcare workers from Melbourne’s Royal Children’s Hospital have been infected with COVID-19. 

They are among 21 hospital staff, including at Melbourne’s Northern Hospital, Bundoora Centre and Broadmeadows Hospital, to have recently contracted the virus.

Seven others who work in clinical and non-clinical roles at the RCH have been forced to self-isolate at home for two weeks.

The RCH would not disclose whether they were close contacts of their five infected colleagues, and rejected the suggestion the cases were part of an outbreak.

Just last Friday, a shop at the hospital was closed after a back-of-house worker tested positive.

As a result of the infections, hospitals are tightening restrictions on visitors.

The virus has also spread among staff at 24 Victorian aged care facilities, eight of which have residents with coronavirus.

It came as Victoria recorded another day of more than 200 cases, with 238 infections on Wednesday.

The state’s death toll rose to 27after a woman in her 90s died of COVID-19.

More than 100 infected Victorians are in hospital, 27 of them in intensive care.

‘Patient zero’ identified

Investigations continue into the movements of a Melbourne freight company worker who travelled to Sydney, as authorities brace for a growing number of cases.

The man attended a work party at the Crossroads Hotel in south-west Sydney, from where the coronavirus has since spread to 34 people.

The man, who has been confirmed as “patient zero” for the cluster, entered NSW on June 30, before its border with Victoria closed.

Six of his colleagues who attended the July 3 work party have since caught COVID-19.

At least 20 infections in the Crossroads Hotel cluster are in patrons, while two are “tertiary” cases (contacts of contacts). 

NSW Premier Gladys Berejiklian has tightened restrictions on pubs and hotels following the outbreak. Photo: AAP

On Wednesday, the Northern Territory also declared all of greater metropolitan Sydney a COVID-19 hotspot. 

“From Friday, if there are any arrivals to the Territory from Sydney, or who have been in Sydney in the previous 14 days, they will be directed into mandatory, supervised quarantine and charged $2500,” Chief Minister Michael Gunner said.

There are similar arrangements for travellers from Victoria.

“It does suck, but it is the way it is,” Mr Gunner said.

The NT will lift border restrictions for people from other states on Friday.

Jail terms for COVID-19 rule-breakers

Queensland will move to jail anyone caught breaking rules to prevent COVID-19 flare-ups as new cases surge in Victoria.

Terms of up to six months behind bars will be introduced to state parliament on Thursday under a legislative amendment.

Fines for individuals have not been enough to stop them from testing the public health directions issued by chief health officer Dr Jeannette Young.

Despite the threat of a visit from police and a huge bills, law-breakers have continued putting lives at risk – many just to party … or play Pokemon Go.

In Victoria, the state worst-hit by current outbreaks, police have fined 546 people since stay-at-home directives were reintroduced for metropolitan Melbourne and neighbouring Mitchell shire last week.

Recent fines included for a party of 34 people at a short-term rental in Docklands, two men playing Pokemon Go and a man who refused to leave a KFC restaurant.

Read more: Victoria Police rake in over $100,000 in fines 

Potential for new cases to emerge

Meanwhile, in South Australia, health officials are waiting on test results to determine if the state has its first new COVID case in more than a fortnight.

A person with a history of overseas travel has been checked for COVID-19 with initial results proving inconclusive.

Results from a second test are expected on Thursday.

The person is in isolation. SA Health said the first test result might indicate an old infection.

-with AAP