A ‘sister’ lineage of Omicron – the Covid variant rapidly sweeping the world – has been detected by scientists.
Experts who detected the strain say it is genetically similar to the super-mutant causing chaos in South Africa.
But one key difference of the Omicron-like subvariant is that it is missing a genetic quirk that allows officials to quickly track its spread, Dailymail reports.
Virologists say the version, currently called BA.2, has already been identified in South Africa, Australia and Canada.
However, no firm details about the near-identical strain are known – and its true origin remains a mystery.
Australian officials raised the alarm about BA.2 last night, saying it was the ‘first in the world’.
It was spotted in a South African man who returned from the country’s Omicron ground zero of Gauteng.
Preliminary analysis suggests it contains its own set of mutations as well as many found in the original Omicron.
In theory, it means BA.2, as the original Omicron, could also be more transmissible than Delta, and possibly able to dodge vaccines.
However, no concrete evidence has yet been published, with BA.2 only thrown into the public spotlight by Queensland health officials last night.
While information is still emerging, one key difference of the Omicron-like lineage is that it can’t be detected almost immediately.
Known as the S gene dropout, this aspect of the original Omicron means it can be detected using a PCR test, as opposed to a more complicated lab analysis.
The fact that BA.2 does not have this S gene dropout means this shortcut cannot be used and is thus harder to track as an outbreak.
Queensland’s health minister Yvette D’Ath confirmed the case in a press conference last night.
We are standing here announcing a new version of Omicron and it’s a first in the world,” she said.
The man, who returned from Gauteng last week, is isolated at a Brisbane hotel quarantine facility and is understood to have a mild case of Covid.
Queensland’s Chief Health Officer Peter Aitken said experts were able to distinguish between the two types of Omicron genetically.
“[They] recognised there are differences between the full and normal Omicron classification, passed it on to the international committee in a really quick time frame. This now led to a re-classification of Omicron.
“It has enough genes to be classified as Omicron, but we don’t know enough about it for what that means as far as clinical severity, vaccine effectiveness. What we do know is that Omicron is more infectious and more transmissible,” Aitken said.
Scientists say BA.2 has now been spotted in genomes submitted by Australia, South Africa and Canada, suggesting it is already spreading in other countries.
The arrival of BA.2 in Queensland came as the Australian state recorded its first case of the original Omicron variant as well.