A five-day lockdown, announced on Friday afternoon, meant her youngest brother would be spending his 21^st birthday at home.

He had planned to celebrate the milestone with family at a Bendigo hotel.

The function would also have served as an opportunity for Mrs Keast's six-month-old son, Kingsley, to meet members of the extended family.

More news: Victoria re-enters lockdown amid new COVID-19 infections

While Mrs Keast said the Stage Four restrictions would hurt, she believed the state government had probably made the right decision.

"Victoria has put in a lot of hard work. I'm a school teacher, so I know it hasn't been the easiest 12 months for anybody," she said.

If five days of pain could prevent the state from reliving months of harsh restrictions, Mrs Keast believed it was worth it.

"As a family with a two-and-a-half-year-old and a six-month-old, we need to be trying to keep ourselves as safe as possible," she said.

"If it's keeping my kids and my family safe, then that's what needs to happen."

That wouldn't make it any easier for Mrs Keast to explain to her daughter, Lila, if the beach holiday the family had planned to embark on later in the week had to be cancelled.

More news: Ablett hopes to speak in Bendigo following five-day lockdown

Announcing the restrictions, premier Daniel Andrews said he was confident the five-day lockdown would be the "circuit breaker" authorities needed to prevent the UK variant of the virus from spreading in the Victorian community.

The highly infectious strain has been detected in cases linked to the Holiday Inn Melbourne Airport outbreak.

"This thing is very different and it presents a different challenge," Mr Andrews said of the UK virus variant.

Chief Health Officer Professor Brett Sutton believed contact tracing would have been "absolutely sufficient" to get on top of the virus if it were an earlier, and less infectious, strain.

The speed with which the UK virus variant was spreading was one of the factors that sparked the five-day lockdown.

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