There are now 19 active Covid cases in the state. Most have been confirmed to be the highly infectious UK coronavirus variant, and there is concern there are more cases in the community.
“Because this is so infectious and is moving so fast, we need a circuit breaker,” Mr Andrews said.
Mr Andrews reiterated the restrictions are not to deal with a third wave of Covid, but to prevent a third wave, reminding the community Victoria is the only place in the world to curb a second wave of the virus.
Addressing the media on Friday, Mr Andrews had a sobering message for the state, given the seriousness of the UK variant of Covid-19, which is substantially more infectious.
“We've built something precious, and we have to make difficult decisions, and do difficult things, in order to defend what we've built,” he said.
“I am confident that this short, sharp circuit breaker will be effective.”
The Australian Open tennis and AFLW games will continue during the lockdown but there will be no spectators. The Australian Open is being treated as a workplace, Mr Andrews said.
What can Victorians do under the five-day lockdown
Victorians will be under ‘Stage Four’ restrictions, starting tonight at 11.59pm until the same time on Wednesday.
There are four reasons to leave your home - for shopping for essential items, caregiving for compassionate reasons, essential work or permitted education and exercise.
The 5km travel rule will also be reimposed.
Masks must be worn indoors and outdoors at all times, except when at home and it is encouraged people work from home if possible.
Intimate partner gatherings are permitted, but private gatherings are not.
Public gatherings are also prohibited, unless for exercise or with members of the same household.
Schools will be closed, but will remain open for vulnerable children and children of essential workers.
Higher education and training is restricted to remote learning only.
Funerals are restricted to no more than 10 guests and those necessary to the service, regardless whether they are indoor or outdoor.
Weddings are not permitted, unless “end of life or exceptional reasons”.
Weddings that are permitted are restricted to five people - the two getting married, the celebrant and two witnesses.
No visitors are permitted at aged care for other residential facilities, with the exceptions of end-of-life reasons.
Visitors are also barred from hospitals, with the exception of end-of-life reasons, to assist a partner for birth or parents accompanying a child.
Care facilities and hospitals will also bar non-essential contractors from entering.
What will be closed for the lockdown
Several services will be closed for the five day lockdown, essential services and supermarkets will remain open.
Non-essential retail will close, and hospitality venues will revert back to take-away only.
Hairdressing and beauty services will close, as will sport venues, though outdoor playgrounds will remain open.
Community sport and outdoor recreation will not be permitted. Exercise is one of the permitted reasons to leave the home, for two hours per day.
Real estate inspections and auctions will not be allowed to go ahead for the next five days, though online auctions can go ahead.
Community venues, including libraries will close, unless they are hosting essential public support services, as will creative studios and entertainment venues.
Alternative to the lockdown is ‘potentially devastating’
All of the new cases announced on Friday are linked to the Holiday Inn at Melbourne Airport.
The outbreak is believed to have stemmed from a family of three who were in quarantine at the Holiday Inn and are believed to have been infected overseas.
One family member, who is now in ICU, used a nebuliser in their room.
Victoria's Chief Health Officer Brett Sutton said the alternative to the lockdown was "potentially devastating".
"I do not want to be here either come Wednesday not having done this and talking about 10, 15, 20, 30 new cases a day, including mystery cases, or including cases that we can't chase down," he said.
"We need to be able to chase each and every case down so that we can get back that precious thing of no community transmission."
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