Finding 'Omicron strain stealth-equipped version', it is more difficult than before to identify mutant strains by PCR test

Further mutated 'stealth-type' strains of the new coronavirus Omicron strain have been discovered one after another in the United Kingdom and Australia. This new Omicron strain is feared to be difficult to identify because it inherits the mutations of the traditional Omicron strain but does not have the genetic features used to quickly identify the Omicron strain in PCR tests.

Omicron Variant: Scientists Discover Version Harder to Detect --Bloomberg
https://www.bloomberg.com/news/articles/2021-12-08/australia-finds-new-omicron-lineage-in-arrival-from-south-africa

Scientists find'stealth' version of Omicron that may be harder to track | Coronavirus | The Guardian
https://www.theguardian.com/world/2021/dec/07/scientists-find-stealth-version-of-omicron-not-identifiable-with-pcr-test-covid-variant

The Guardian, a large British letter, reported on December 7, 2021 that an Omicron strain of the new coronavirus, which is difficult to identify by PCR, was discovered. The Omicron strain, discovered in South Africa in November 2021, has the feature of 'S gene dropout ' in which one of the three genes targeted by many PCR tests is not detected, so the other ones at the PCR test stage. It was easily distinguishable from the new coronavirus. However, the newly discovered Omicron strain does not have the S gene dropout, making it difficult to identify mutant strains by PCR.

Following this discovery, researchers named the new Omicron strain 'BA.2' to distinguish it from the traditional Omicron strain 'BA.1'. In addition, some researchers informally call it 'stealth type' because it is difficult to identify by inspection.

Vinod Scaria, a biologist at the Genomics and Integrated Biology Institute of the Scientific and Industrial Research Council in India, said the discovery of the BA.2 strain of Omicron 'needs to be scared because it is meant to enhance epidemiological surveillance. There is no such thing. '

???? The B.1.1.529 #Omicron lineage is now split to BA.1 and BA.2 .BA.1 will now have the original lineage and BA.2 will encomapss the new outlier with around 24 mutations.

???? PS: This is for better epidemiological surveillance & nothing to be scared yet. Https://t.co/4y1RVf5Ej8

— Vinod Scaria (@vinodscaria) December 7, 2021

Emma Hodcroft, an epidemiologist at the University of Bern, Switzerland, commented on the effectiveness of the PCR test: 'BA.2 does not use the'tricks' using the S gene dropout, but the PCR test itself continues to work. I explained.

One key mutation that BA.2 is missing is the S: 69 / 70del --the one that causes the SGTF / S-drop-out. This means we can't use this'shortcut' to find possible Omicron cases * for BA .2 only *. However, * the PCR test itself still works! * You'd test + for SARS-CoV-2.

6 / N

— Dr Emma Hodcroft (@ firefoxx66) December 7, 2021

Following the discovery in the United Kingdom, Peter Aitken, Deputy Chief Health Officer of Queensland, Australia, held a press conference on December 8th, saying, 'I entered from South Africa and got a positive reaction for the new coronavirus on the 4th. A new strain of Omicron strain was discovered by a traveler who was there. ' According to Aitken, the new strain of Omicron has 14 of the more than 30 mutations in the Omicron strain, but does not have the S gene dropout.

It is unclear at the time of writing whether the new Omicron strain found in Australia is the same as BA.2 found in the United Kingdom, but it is common in that it does not have an S gene dropout.

Aitken commented on the discovery of the new Omicron strain in Australia, 'it will help people realize that Omicron strains can be endemic in all regions.'