WASHINGTON (Washington Insider Magazine) -Omicron (or BA.1) has swiftly become the main COVID-19 viral subtype since its appearance in late 2021. It was more communicable than the Delta variant due to the mutations it carried, allowing it to spread quickly through people all over the world. It has been discovered that it causes a milder sickness than Delta – albeit milder shouldn’t be confused with mild.
Scientists are now monitoring a subgroup of the Omicron variant called BA.2, which was first discovered in late December 2021 in India and South Africa. It has now been discovered in the United States and Europe. When compared to BA.1, the subvariant is expected to have 20 more mutations on its spike protein, though scientists are unsure what this means for the pandemic’s trajectory. There isn’t enough evidence yet to say if BA.2 causes more severe sickness than BA.1.
BA.2 is referred to as the “stealth” variant by some people since it is said to be difficult to detect using PCR and lateral flow tests. This is not the case; it is possible to identify it by both the tests.
When PCR tests are used to detect the SARS-CoV-2 virus, they look for three distinct DNA sequences and will indicate a positive result if at least two of them are present. The S-gene, which is present on the spike protein, is one of the sequences that the test looks for. This is known as the “S-gene dropout” in the BA.1 Omicron variation; PCR testing will still show a positive result since it will detect the other two DNA sequences they are supposed to identify. However, the lack of the S-gene made it easier for scientists to distinguish between BA.1 Omicron and Delta, which both possessed the S-gene.
The BA.2 Omicron form, like Delta, has the S-gene, making it difficult for scientists to distinguish between the two, hence the term “stealth” variant.
However, because Omicron is currently dominant and Delta is rapidly disappearing, any PCR tests that detect the presence of the S-gene in the future will very certainly be for the BA.2 subvariant of Omicron.
Denmark has seen a dominance of this variant. The rapid rise in instances there and in other nations such as the United Kingdom implies that BA.2 is more transmissible and capable of outcompeting the BA.1 variant. A recent study of Omicron subvariant transmission in Danish households discovered that the BA.2 subvariant is significantly more communicable than the original variant.
Between 20 December 2021, and 11 January, 2022, the study looked at families in Denmark where one person tested positive for Omicron. They had 2,122 BA.2 positive people and 6,419 BA.1 positive people. The researchers then monitored these individuals to determine if they passed on their Omicron sub variants to other members in the family.
Upon comparison to the BA.1 subvariant, the BA.2 subvariant transmitted more among both vaccinated and unvaccinated members of the household. However, they discovered that people who had not been vaccinated were more likely to transmit BA.2 than those who had been.
