World Health Organisation leaders say many countries have not reached their peak in cases of the highly transmissible Omicron variant of the coronavirus.

The WHO cautioned against lifting all restrictions – like would be the case in a so-called “let it rip” scenario – warning that leaders must be ready to snap back into protection mode to fight the “dynamic” virus.

“Many countries have low levels of vaccination coverage with very vulnerable individuals within their populations,” WHO’s COVID-19 technical lead Maria Van Kerkhove told an online briefing on Wednesday morning.

“And so now is not the time to lift everything all at once.”

Dr Van Kerkhove added: “We have always urged, always (be) very cautious, in applying interventions as well as lifting those interventions in a steady and in a slow way, piece by piece….this virus is quite dynamic.”

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WHO Director-General Tedros Adhanom Ghebreyesus said the United Nations agency was concerned about a narrative taking hold in some countries that “because of vaccines, and because of Omicron’s high transmissibility and lower severity, preventing transmission is no longer possible, and no longer necessary”.

“Nothing could be further from the truth,” Dr Tedros told the briefing.

“More transmission means more deaths.

“We are not calling for any country to return to so-called lockdown. But we are calling on all countries to protect their people using every tool in the toolkit, not vaccines alone.”

He added: “It’s premature for any country to surrender or to declare victory.”

Tweet from @mvankerkhove

WHO’s emergencies chief Mike Ryan, addressing the same briefing, urged countries to chart their own path out of the pandemic and not blindly follow others in relaxing measures.

“Those countries who are making decisions to open up more broadly also need to be sure of capacity to reintroduce measures, with community acceptance, if needed,” Dr Ryan said.

“So as if we open the doors quickly, you better be very well able to close them very quickly as well.”

Denmark and Austria last week became the latest countries to relax COVID-19 restrictions, after similar moves by the United Kingdom, Ireland and the Netherlands although other European countries planned new curbs to battle record numbers of infections.

In a separate online briefing earlier on Tuesday, Dr Boris Pavlin of the WHO’s COVID-19 Response Team said the emerging BA.2 form of Omicron does not seem to be any more severe than the original BA.1 form.

BA.2, being nicknamed the “stealth” subvariant, has been detected here in Australia.

Overall case numbers were stable nationwide on Tuesday, with another 35,198 infections recorded.

Victoria had the most deaths with 34, followed by New South Wales with 30. Ten people died in Queensland and three in South Australia.

Minister to face questions over COVID response

On Wednesday, the government’s handling of COVID-19 in aged care will be put under the microscope when a parliamentary committee meets in Canberra.

Aged Care Minister Richard Colbeck will be grilled by senators following large COVID-19 outbreaks at nursing homes across the country, as well as shortages of rapid antigen tests and protective equipment for staff.

It was revealed last month the minister said he was unable to attend a COVID-19 committee hearing on the same day he attended the Ashes Test match in Hobart.

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Senator Colbeck originally said he didn’t attend the previous committee meeting because he did not want to divert health department officials from urgent work.

Prime Minister Scott Morrison has since defended Senator Colbeck, while indicating he understood the criticism the minister faced in light of the incident.

Officials from the Department of Health, including chief medical officer Professor Paul Kelly, will also be questioned at Wednesday’s hearing, along with members of the medical regulator and leading advisory group on vaccinations.

The COVID-19 committee meeting comes off the back of the government offering $400 cash bonuses to aged care staff as retention payments.

Mr Morrison denied the payments were being used as a pre-election sweetener for the aged-care sector, which has been heavily impacted by the pandemic.

“What we’re doing here is helping the aged care providers give that support to aged care workers during this pandemic to be able to keep them there working in those facilities,” he said.

“That’s what it’s designed to do, and we know it was effective last time and we believe it will be effective again and it needs to happen now.”

Since the start of the Omicron wave of COVID-19 cases, there have been 566 virus-related deaths in aged care.

The sector has been hit hard by staff shortages due to the large number of cases in aged care facilities and workers needing to isolate.

Opposition Leader Anthony Albanese said he would support making a case to the Fair Work Commission to increase the rates of pay for aged-care workers, rather than a lump sum payment proposed by the government.

“The problem here is this (bonus) is a cash payment in the lead up to an election with no sustainable increase in their pay,” Mr Albanese said.

“Why is the government not providing support for aged-care workers on a permanent basis?”

-with AAP