Chief Health Officer Brett Sutton said regional Victoria is "under threat".

"It's likely with the significant movement, for essential reasons, to have gone beyond Shepparton," he said.

"That's why we have declared that all the current restrictions in Metropolitan Melbourne will apply, other than the curfew, to regional Victoria."

Restrictions will be in place until September 2.

Mr Sutton said it was a difficult day for Victoria.

"We have really significant challenges with the Delta variant," he said.

The government recommends all primary school aged children wear masks to protect themselves.

PREVIOUSLY:

Regional Victoria has once again been plunged into lockdown.

From 1pm today, regional Victoria will be returned to lockdown in line with Melbourne but will not be subject to the curfew.

Victorian Premier Daniel Andrews said the Shepparton outbreak was 'very concerning' and there was evidence of cases travelling to other parts of regional Victoria including Bendigo.

"Sadly the public health team has advised given the Shepparton outbreak... there is a very significant risk of transmission right across Victoria," he said.

It's the first time Albury and Wodonga have both been locked down at the same time since the national lockdown from March to May 2020.

An authorised worker permit system will be introduced in regional Victoria.

A permit system is being introduce to access childcare across Victoria, with only children of essential workers and children with certain needs able to attend childcare.

Victoria recorded 61 cases of COVID in the 24 hours to midnight, of which 39 were infectious while in the community.

IN OTHER NEWS:

48 of the cases are linked to known outbreaks, 13 are mystery cases.

The Department of Health said an additional 16 local cases - all from Shepparton - had been recorded on a rapid PCR testing platform and would be reported in tomorrow's numbers.

Across the border Murrumbidgee Local Health District has revealed a Lachlan Shire resident has tested positive to COVID-19.

It comes as 17 cases of COVID were detected in Shepparton, days after COVID fragments appeared in the town's wastewater.

The source of the infection and how it reached Shepparton is still unknown.

The outbreak is expected to grow as more test results are returned.

Yesterday, Mr Andrews refused to rule out locking down regional Victoria.

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