Countries all over the world are scrambling to shut their borders to UK travellers and keep out a new highly contagious coronavirus strain.

The mutant variant was first detected in the UK in September and now accounts for about 70 per cent of new COVID-19 cases in the country.

Experts estimate the new strain is between 40 and 70 per cent more infectious than other strains.

Epidemiologist from the University of South Australia, Professor Adrian Esterman, says it’s possible the mutant strain is already present in other countries.

“We don’t know whether it’s in other countries as well because the UK does lots of genomic testing. They do the most genomic testing in the world.,” he told Tony Jones, filling in for Neil Mitchell.

“Other countries don’t do anywhere near as much testing.”

Two returned Australians in hotel quarantine in NSW, who have travelled from the UK, have the new strain of the virus.

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