Developed nations such as Australia have been warned slamming borders shut to countries reporting new COVID-19 variants could backfire.

The World Health Organisation says it could make countries less willing to share information about emerging strains.

“We don’t like to see that level of restriction because that really punishes (those countries),” WHO spokeswoman Margaret Harris told Sky News on Tuesday.

“It makes other countries less comfortable about being so helpful to the rest of the world.”

Australia has delayed it reopening to international students and visa holders from Wednesday until December 15 to buy time to find out more about the Omicron variant that appears to be more transmissible.

“More time was needed to make sure that we had all the relevant information in relation to that variant,” Home Affairs Minister Karen Andrews told ABC TV.

“We understand how difficult it is to get the skilled labour needed by so many businesses here in Australia and of course we want to welcome back international students as soon as possible.

“This is a 14-day pause whilst we gather the information that we need about this particular variant.”

Australia’s border is already shut to eight nations in southern Africa where the strain was first detected.

Federal, state and territory leaders are meeting for national cabinet on Tuesday to look at quarantine arrangements after Victoria, NSW and the ACT mandated all international arrivals to Australia isolate for 72 hours.

Victoria also reintroduced mandatory two-week quarantine for close contacts of Omicron cases regardless of their vaccination status.

The federal government is considering whether to bring forward booster shots currently recommended for six months after a second dose.

But Health Minister Greg Hunt says there is no time frame on when the Australian Technical Advisory Group on Immunisation will report back. 

Nearly 87 per cent of Australians aged 16 and older are fully vaccinated.

The Business Council of Australia wants to see consistent health responses across states and territories.

“If we’re acting on health advice, then why isn’t that consistent in each state?” chief executive Jennifer Westacott told ABC radio.  

“Everyone assumes that we’re going to have more mutations, more variants on this. Let’s get the systems in place.

“It’s not too late to stand these things up whether it’s dedicated quarantine facilities or whether it’s particular systems that industry pays for so that we can keep things moving and get momentum into the economy.”

By Georgie Moore in Canberra

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