NEW CASES: 243 (up from 214 yesterday)

ACTIVE CASES: 1034 (up from 992 yesterday)

Ballarat's active COVID case count has jumped back above 1000 for the first time in four days.

There are now 1034 active COVID cases, according to the health department.

However, the actual numbers are guaranteed to be much higher as rapid tests are not counted in location data.

There were 243 new cases confirmed in the 24 hours to midnight last night.

The average case count in Ballarat over the past seven days 209.5 per day, compared to 218.5 for the seven days before that, suggesting a slowing down in the spread of the virus.

VICTORIAN COVID UPDATE | Friday, January 21

NEW CASES: 18,167 (down from 21,966 yesterday)

DEATHS: 20 (up from 15 yesterday)

ACTIVE CASES: 252,399 (up from 246,894 yesterday)

IN HOSPITAL: 1096 (down from 1,206 yesterday)

IN ICU: 121 (down from 122 yesterday)

ON VENTILATOR: 34 (down from 40 yesterday)

Victoria has recorded 18,167 new COVID-19 cases and 20 deaths, as a four-day booster vaccine blitz gets underway at eight state-run hubs.

The new infections, confirmed by the health department on Friday, include 10,023 from PCR tests and 8144 from rapid antigen tests.

It takes the total number of active cases in the state to 252,399, up by 5505.

However, hospital figures have dropped by 110 to 1096, ahead of the state's expected peak during the Omicron wave.

The number of Victorians in intensive care sits at 121 and there are 34 people on ventilation.

Victoria's third dose rate has lifted to 28 per cent as the booster blitz begins on Friday, with 60,000 vaccine slots available.

In Ballarat, the spread of COVID has remained relatively steady for the past two weeks.

The number of new cases reported each day has hovered between 124 and 283 for the last 15 days.

The number of active cases also hovers around the 1000 mark, according to the health department.

However, the actual numbers are guaranteed to be much higher as rapid tests are not counted in location data.

Meanwhile, federal police have launched an investigation into the price gouging of rapid antigen tests.

A specialist taskforce has been set up by the AFP, after investigations began in NSW and Queensland following referrals from the consumer watchdog.

Retailers caught price gouging on the tests have been warned they will face five years in prison.

AFP assistant commissioner of the crime command, Nigel Ryan, said there would be a zero-tolerance approach to retailers.

"The AFP will use its full powers to crack down on RAT price gouging," he said.

"Not only is price gouging of RATs unethical but it is illegal, and the AFP will use its significant resources to ensure it protects the public from the unlawful greed of others."

While referrals have been made by the Australian Competition and Consumer Commission in NSW and Queensland, the AFP said it expects more referrals to be made.

Charges would be laid for businesses and individuals if the rapid tests are sold for more than 20 per cent of their original retail price.

Strike teams will have the power to force people caught price gouging to surrender the rapid tests, where they will be used as part of the national medical stockpile.

No rapid tests have yet been seized to go into the stockpile.

Assistance commissioner Ryan said Commonwealth and state agencies would be working together on the investigation.

"Those who breach the law face penalties of up to five years in jail or a $66,000 fine," he said.

"My message is clear: do not risk jail time or a significant fine for a few extra dollars."

The consumer watchdog said it had heard reports of rapid tests costing between $20 and $30 for a single test, despite wholesale costs ranging up to $11.95. In one instance, a test was sold for more than $70.

The ACCC received more than 1800 reports across the country, as widespread shortages of rapid antigen tests remain due to rising cases of the Omicron variant.

The taskforce follows reports from businesses that rapid tests were being requisitioned by the federal health department, claims the department has categorically denied.

Prime Minister Scott Morrison said on Thursday the claims were false.

"If you're being told by a supplier that you can't get those rapid antigen tests because the Commonwealth government has redirected, it's not true," he said.

- with AAP

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