Here's the latest variant picture for BA.2 (Omicron). Globally it is far less common than it's sibling BA.1 lineage. BA.2 has many unique mutations.
The frequency of BA.2 is rising in several countries, on similar trajectories.
(Linear then log scales)
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I'm now presenting these charts with both a linear Y-axis scale, together with a version using a log scale. A log axis helps compare growth rates.
The Frequency is calculated for each country independently, comparing to all the recent samples sequenced in that country.
Here are the other top countries in Europe, by BA.2 samples.
Although their frequencies are lower so far, Belgium, France, Germany, Norway and the Netherlands appear to be on a similar trajectory.
Here's a full variant picture for India. IMO the recent results for BA.2 need to be considered in the context that:
- recent sample sizes are very low (grey column chart)
- possible founder effects - relatively late start to their Omicron outbreak.
Here are the Indian states reporting the most BA.2 samples.
Note the recent steep rises in frequency have been dominated by Gujarat and Telangaina, so the recent national picture for India might only be representative of a few cities.
In Denmark, it seems that BA.2 has been out-competing BA.1 for some weeks now.
There are some anecdotal reports of re-infections of BA.2, especially among those relying on natural immunity from Delta or BA.1.
Similarly, the picture for Singapore shows BA.2 apparently out-competing BA.1.
In the UK, the three largest countries recently show BA.2 on a similar very steep trajectory.
Here's an analysis of cases and deaths, for Australia, then state-by-state.
I couldn't bear to post this last week as the case rate was one of the worst in the world (with WA at near-zero). That seems to have been the peak.
The death rate continues to increase.
New South Wales is the worst affected state, where the case rate rose to just under 4,000 per 100K population. If NSW was a country, that would've been the highest rate globally for any comparable country.
Victoria rose to a similar level, just slightly lower on this "per population" basis.
The rise in cases was even steeper than in NSW, so the impact of that on deaths is likely yet to come.
The Australian states each have fairly discrete outbreaks with quite different profiles.
Here's New South Wales, where NPIs were first dropped as BA.1 arrived, and multiple super-spreader events in mid-December. Together that paved the way for the total dominance at ~95%.
Here's the latest variant picture for BA.1 (Omicron) with the Spike R346K mutation. That mutation helps with immunity escape.
This combination was recently identified as a new sub-lineage BA.1.1, but that will take some time to filter through to databases and websites.
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The global analysis (above) of BA.1 with the Spike R346K mutation shows it's frequency was low, but has been steadily increasing (as a proportion of all BA.1 samples).
In the United Kingdom, the frequency of BA.1 with the Spike R346K mutation has been steadily growing, recently at ~25% (of all BA.1 samples).