Omicron BA.2 Variant, is this going to be another wave?
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Original omicron, B.1.1.529
PANGO Lineage is described as a cluster of sequences that are associated with an epidemiological event,
Phylogenetic Assignment of Named Global Outbreak Lineages (PANGOLIN)
Omicron includes Pango lineage B.1.1.529 and descendent Pango lineages BA.1, BA.1.1, BA.2 and BA.3.
BA.2 is a descendent lineage
Identified, Philippines, then to India
Omicron sublineage BA.2
10,000 cases of BA.2, 40 countries
Potentially increased transmissibility over omicron clade BA.1
U.K. Health Security Agency, VUI
Cases doubling every 4 days
120% growth advantage over original Omicron clade
(Delta to Omicron, 500% growth advantage)
Similar growth, Denmark, Norway, Sweden, India
Does not have the same s-gene target failure on PCR as omicron BA.1
BA.2 is S gene positive
BA.1, 60 mutations
BA.2, 80 mutations
Meaghan Kall, UKHSA
Yes, BA.2 is increasing in the UK 🇬🇧
It may have a slight growth advantage but no evidence at all yet that it can evade Omicron (BA.1) immunity or be different to Omicron in any meaningful way.
Variants will continue to emerge, but not all variants will be a problem.
— Meaghan Kall (@kallmemeg) January 23, 2022
no evidence at all yet that it can evade Omicron (BA.1) immunity or be different to Omicron in any meaningful way
Variants will continue to emerge, but not all variants will be a problem
Only having a transmissibility advantage at this stage of the game (with population immunity so high) isn’t a total showstopper
Little difference in vaccine effectiveness between BA.1 and BA.2
Disease severity, comparable to BA.1
Unlikely to be another BA.2 omicron wave
BA.2 now accounts for 65% of new cases
Early data, not been associated with an increase in hospitalisations
Increase in BA.2 in Oslo
Concurred that BA.2 is likely more contagious than BA.1.
Can those infected with the BA.1 get re-infected with BA.2.
French Health Minister, Olivier Veran
What we know for now is that BA.2 more or less corresponds to the characteristics that we know of Omicron
Robert Garry, virologist Tulane University School of Medicine
Variants have come, variants have gone
I don’t think there’s any reason to think this one is a whole lot worse than the current version of omicron
James Musser, Center for Molecular and Translational Human Infectious Diseases Research, Houston Methodist
The good news is we have only three
We certainly do not see the 5% and more reported in the U.K
Certainly not the 40% in Denmark
We know that omicron … can clearly evade preexisting immunity,
from both vaccines and exposure to other variants of the virus,
What we don’t know yet is whether son-of-omicron does that better or worse than omicron.
So that’s an open question.
Anders Fomsgaard, virologist, State Serum Institute Denmark
BA. 2 has become the dominant form of the virus in his nation of nearly 6 million people,
where it now accounts for about 65% of new cases
as BA. 1 is on the decline
we are not so concerned, since we so far do not see major differences in age distribution, vaccination status, breakthrough infections and risk of hospitalization.
Also, despite the high infection rate of BA. 2, the numbers in ICUs are decreasing
Francois Balloux, professor of computational biology, University College, London
BA.2 about 20 mutations apart from the original BA.1
the two omicron sub lineages are sister clades that split from other several months ago, and are not derived from each other
People infected with one of the lineages would have “robust immunity” against the other one
At this stage, BA.1 and BA.2 can be considered as two epidemiologically largely equivalent sub-lineages of omicron