MELBOURNE (BLOOMBERG) - Australia's Queensland state has found a new Omicron lineage in a traveller who arrived from South Africa, the health authorities said on Wednesday (Dec 8).
The new lineage has about half the gene variations of the original Omicron variant and cannot be detected with typical screening, the state's acting chief health officer Peter Aitken told reporters.
It was found in a traveller who had arrived from South Africa and tested positive for the coronavirus last Saturday, he said.
Dr Aitken said the new lineage has enough markers for the authorities "to be able to classify it as Omicron", but they do not know enough about it as to what that means as far as clinical severity and vaccine effectiveness are concerned.
"We now have Omicron and Omicron-like," he said.
The discovery comes as Queensland prepares to finally reopen its border to the rest of Australia ahead of schedule next Monday, as more than 80 per cent of the eligible population will be fully vaccinated later this week.
The discovery may be a setback for scientists racing to understand the full impact of the Omicron variant, including how virulent the strain is and whether vaccines are effective at reducing the risk of severe disease.
Although most genetic changes are innocuous as viruses mutate, some can make the mutant more adept at infecting cells, for example, or evading antibodies.
The new lineage has about half, or 14, of the genome mutations of the conventional Omicron variant and does not have the S gene dropout feature, making it harder to track through polymerase chain reaction testing, Dr Aitken said.
The discovery is "going to lead to improvements in people recognising potential spread of Omicron in all communities", he said.