More than 1000 Australian Defence Force troops were expected to be on the ground from Thursday, monitoring hotel quarantine as well as providing logistical and medical support for the state's coronavirus testing blitz.

But plans to have 850 ADF members involved in hotel quarantine are being revised.

"Our top priority is on planning and logistics assistance, and medical personnel to support our suburban testing blitz," a state government spokeswoman said.

"We are finalising our plans for hotel quarantine, including any additional roles the ADF might be able to play."

Victoria recorded another 33 COVID-19 cases on Thursday, giving new impetus to the testing blitz, which aims to reach 50 per cent of residents in 10 virus hotspots.

Keilor Downs, Broadmeadows, Maidstone, Albanvale, Sunshine West, Hallam, Brunswick West, Fawkner, Reservoir and Pakenham all have high rates of community transmission.

"The first three days are solely focused on Keilor Downs and Broadmeadows, but we will move to the balance of those suburbs over the course of a 10-day period," Premier Daniel Andrews said on Thursday.

About 10,000 residents will be tested each day in the 10 suburbs by 800 staff in a fleet of mobile testing vans.

Victoria has been processing 18,000 tests a day, but that will ramp up to 25,000, with NSW, South Australia, Tasmania and Queensland helping to process the virus tests.

"This is a public health bushfire and when it comes to the bushfires, we always work together," Mr Andrews said.

Opposition Leader Michael O'Brien blamed the need for the testing blitz on government failings, claiming the premier had to be "dragged kicking and screaming to get the ADF in".

"Daniel Andrews has been very quick to blame Victorian families for the spread of the coronavirus," Mr O'Brien said.

"I think his government needs to actually look in the mirror and look at the mistakes that they have made."

Of the 33 new cases, seven are returned travellers, nine are linked to known and contained outbreaks, six emerged after routine testing and the origin of another 11 cases are under investigation.

Thursday's figure is the highest daily number of new cases in Victoria since the surge started last week.

Victoria's active cases jumped from 58 to 143 in the period June 17-24, while the rest of the country combined only had an increase of 20.

Victorian Chief Health Officer Brett Sutton said a review of the training received by security guards in hotels hosting returned travellers was under way.

He added testing in hotspot areas had stepped up in the past week.

Community engagement in the local government areas of Brimbank, Casey, Cardinia, Darebin, Hume and Moreland has also been ramped up after they were identified as coronavirus hotspots.

These areas have large migrant populations, with many speaking languages other than English at home.

Information about the virus has been translated into 55 languages, but the government has conceded it has to work harder to reach people.

Since the spike in new cases, drive-through testing sites have experienced extremely high demand and panic buying has also returned, with Coles and Woolworths reinstating purchase limits on items like toilet paper.

Australian Associated Press