Workers from multiple hospitals and aged-care centres across Melbourne have been confirmed with the coronavirus as Victoria confirms another 165 infections.

Of the new cases reported on Thursday, the first day of a six-week Melbourne-wide lockdown, chief health officer Brett Sutton confirmed just 30 were linked to known outbreaks while 135 were still being investigated.

They include 18 more in the Flemington and North Melbourne public housing estates that have been locked down since Saturday. There are now 111 cases linked to the high-rise towers.

All 3000 residents of the estates have been tested for COVID-19 since Saturday. They remain in lockdown until their results come back.

Victorian Premier Daniel Andrews was expected to provide an update on the situation at the towers later on Thursday.

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It is the fourth day of new cases in the triple-digits, with Victoria’s overall total now at 3098. It has more than 900 active cases, up from fewer than 50 just four weeks ago.

Cases from the Victorian outbreak have also spread into NSW, with three people in the border city of Albury confirmed with the virus on Thursday.

Albury residents have been urged to get tested if they have even the most mild symptoms.

The Royal Melbourne Hospital is just one of several where staff have contracted the virus. Photo: AAP

On Thursday, Victoria’s Department of Health and Human Services said two healthcare workers from the Royal Melbourne Hospital had tested positive for the virus.

Two people who work in Sunshine Hospital’s emergency department, in Melbourne’s west, have also contracted the virus.

An outbreak at the Northern Hospital in Epping has risen to 11 infections, including nine staff members and two household contacts, after another worker returned a positive test.

A number of Northern Hospital staff are already in quarantine and ambulances have been diverted from the normally busy emergency department.

There are also confirmed cases linked to aged-care facilities, which are in lockdown. They are:

• Two staff members from Menarock Life Aged Care in Essendon
• One employee who worked while infectious at each of BaptCare’s The Orchards Community in Doncaster, Benetas’ St George’s in Altona Meadows and BlueCross, Ivanhoe
• One staff member who worked while not infectious at Aurrum Aged Care facility and another at Holmwood Aged Care facility, both in Healesville.

In another concerning development, six of the new cases are linked to an outbreak at Al-Taqwa College at Truganina, in Melbourne’s outer west.

It has become the state’s biggest cluster, totalling 113 people.

The first case at the school was identified on June 27, with more than 2000 students and hundreds of staff sent into quarantine.

“We regret to report that a number of our staff and students have tested positive for COVID-19,” college principal Omar Hallak wrote in a Facebook post on Sunday.

He said the school had done everything it could to prevent the spread of the virus, including daily temperature checks for all students.

“We have tried our utmost best to prevent having any cases in our school,” he said.

“However, unfortunately, this is out of our hands, as it is with quite a few other schools around Victoria, around the nation and around the world, which is quite saddening.”

Temperature checks will be introduced Melbourne-wide when senior students return to school from July 13.

State Education Minister James Merlino said on Thursday that more than 14,000 thermometers will be sent to schools in the 32 locked-down local government areas.

Families will be encouraged to seek COVID testing or the advice of healthcare professionals if a student has a temperature of 37.5 degrees or above.

Only senior secondary students, year 10 students who study VCE subjects, children of essential workers and those attending specialist schools will return to face-to-face learning on Monday.

School holidays for all other students in Victoria’s locked-down areas have been extended for a week while teachers and parents prepare for a return to online learning.

Five million people in metropolitan Melbourne and one adjacent local government area began a six-week lockdown on Thursday.

It will not end until at least mid-August.

-with agencies