An aged-care worker at a facility in Melbourne’s west has been diagnosed with COVID-19, sending the home into lockdown.

The team member at Arcare Maidstone was not showing symptoms when they last worked at the home on May 27, but later tested positive.

The facility says the worker had their first dose of a COVID-19 vaccine, as had a “significant number” of the residents.

No other cases have been linked to the facility.

“I want to assure you that, whilst we hoped that this would not happen again, we are well prepared, and our infection control practices put us in a good place to manage this outbreak effectively,” Arcare CEO Colin Singh said in a letter to residents and families.

The state recorded five new locally acquired cases of COVID-19 on Saturday.

The outbreak from Melbourne’s northern suburbs grew to 35 on Saturday.

Authorities are expected to reveal later today whether the latest cases are linked to that cluster.

The five local infections and an overseas-acquired case in hotel quarantine were detected from 45,301 test results processed on Saturday.

There are now 45 active infections in the state, including those in hotel quarantine.

As the outbreak has grown, more than 170 exposure sites have been listed on the health department’s website.

Overnight, the busy Chadstone Shopping Centre and St Kilda restaurants were added to the list, which also includes five pubs and bars of “significant” concern and a dozen venues visited by an infected delivery driver over the space of a week.

South Australian origin

The outbreak ultimately started with a Wollert man who contracted the virus in a South Australian quarantine hotel. However, health teams are still yet to directly link him to the other cases in the cluster.

The growing outbreak and large list of high-risk exposure sites prompted the snap lockdown, which was announced for the whole state on Thursday.

The lockdown is due to end at 11.59pm on Thursday, June 3, but authorities have warned it is a “day-by-day proposition” as to whether it will end on schedule.

After the last snap lockdown in February, some mask rules and gathering restrictions remained in place even after the bulk of the lockdown ended.

There were 17,702 vaccine doses delivered in state-run centres on Saturday.

Victoria broke its own vaccination records on Thursday and Friday, prompted by the outbreak and the rollout expanding to allow 40 to 49-year-olds to receive the Pfizer vaccine.

High demand for the shots has seen the booking hotline crash three days in a row.

On Saturday, technical issues with the booking systems at two of the state’s busiest mass-vaccination hubs saw people waiting in stationary lines for hours and walk-ins being turned away.

Late on Saturday afternoon, an online booking portal appeared briefly on the health department’s website, allowing some eagle-eyed Victorians to book an appointment.

But the health department said the online booking system was still in test mode and would be available to use soon.

Those who managed to make a booking during the testing of the portal will have their appointments honoured.

The website was live for a number of hours, but has not been officially launched.

–ABC