Premier Daniel Andrews says up to 30 visitors will be allowed to gather at homes each day from 11.59pm on Friday, while outdoor gatherings of up to 100 people will be permitted in public places.

Masks must be carried at all times but only need to be worn on public transport, in taxis and ride-share vehicles, in aged care facilities and at indoor shopping centres and other crowded places.

A density limit of one person per two square metres will remain in place in pubs, restaurants and nightclubs and at beauty services, funerals, weddings and community facilities as long as a QR code system is in place.

Retail businesses will have the same density cap, with electronic record-keeping recommended.

Gyms, meanwhile, will have a density limit of one person per four square metres, with classes limited to 50 people indoors and 100 outdoors.

For the first time since the start of the pandemic, 75 per cent of both public and private sector workers will be allowed to return to the office.

Crowds will also return to the MCG and Marvel Stadium at 50 per cent capacity for round one of the AFL.

The Victorian Racing Club has announced up to 15,000 fans can attend Saturday's Australian Guineas Day and Super Saturday next weekend at Flemington.

The settings largely reflect those that were in place across the state at Christmas.

Restrictions were then tightened over the New Year period following the Black Rock cluster, before they were relaxed in late January.

In early February they were tightened again after a hotel quarantine worker from the Grand Hyatt contracted COVID-19.

A week later, the state entered a five-day "circuit-breaker" lockdown, due to an outbreak at the Holiday Inn at Melbourne Airport.

Some restrictions, including mask-wearing and strict gathering limits, have remained in place since the lockdown ended last Thursday.

Friday's two new cases, which broke Victoria's six-day run of no infections, were also linked to the Holiday Inn outbreak.

Mr Andrews said the duo were close contacts of pre-existing cases and had been in hotel quarantine during their infectious period.

"They pose no risk to public health," he said.

The outbreak, which now totals 24 cases, can be traced back to a family of three staying at the quarantine hotel in early February, who contracted the highly infectious UK virus strain overseas.

More than 3500 close contacts of positive cases have been self-isolating for two weeks.

The state's testing chief Jeroen Weimar confirmed most will end quarantine on Friday.

Opposition spokesman David Davis urged the government to release public health advice for the latest set of restrictions, including the 30 person household gathering limit.

"Where does the number come from and why is it tougher than other states?" he asked.

Meanwhile, federal health authorities have decided to throw out up to 150 doses of Pfizer vaccine after concerns they had been left at the wrong temperature and become spoiled.

It's understood aged care residents at St Vincent's Care Services Werribee were vaccinated this week, with 25 vials of vaccine left over.

It's the second bungle for Australia's coronavirus rollout, which is in its first week, with the federal government in charge of distributing the vaccine in aged care.

Mr Andrews said 2900 shots have been administered to frontline health workers and hotel quarantine staff in Victoria.

Some 16,594 coronavirus tests were processed in the 24 hours to Friday morning.

Australian Associated Press