I've run preliminary @nextstrain focal builds on 20B/S:796H (B.1.1.318) (pictured) & 20A/S:210T (B.1.619).

These aren't part of CoVariants (yet?) but they've caught a couple eyes and I thought it was worth taking a closer look.

1/8 Image
20B/S:796H (B.1.1.318) is behind most of the recent increase in 'other' variants circulating in Greece (shown in grey on the CoVariants plot, below - disregard last point, low sequence #'s).

It's very prominent in Greece, but also found worldwide.

2/8

nextstrain.org/groups/neherla… ImageImage
Taking a closer look at Europe only, we can see there's a large cluster in Greece, but also distinct clusters in Switzerland & Ireland, & many sequences from other countries scattered between.

3/8

nextstrain.org/groups/neherla… Image
20B/S:796H (B.1.1.318) has spike mutations at S:95I, S:144-, S:484K, & S:681H which are shared with other Variants of Concern/Interest.

The distinct clusters in Switzerland, Greece, & Ireland generally don't have additional spike mutations.

4/8

covariants.org/shared-mutatio… ImageImage
The fact that the significant recent cluster in Greece (or the others) doesn't have additional spike mutations suggests (but doesn't rule out) that this expansion may *not* be due to viral changes.

A reminder that it's not just the virus that determines transmission!! 🧑🏽‍🤝‍🧑🏻

5/8 Image
20A/S:210T (B.1.619) was initially mostly seen in Africa & Europe & seemed to be decreasing in frequency, but has recently grown again, particularly in South Korea.

6/8

nextstrain.org/groups/neherla… Image
Looking just at Europe & Asia, we can see clusters in Germany, Switzerland, France, & Belgium, as well as the large South Korean cluster clearly.

7/8

nextstrain.org/groups/neherla… Image
20A/S:210T (B.1.619) has a number of spike mutations, but only S:484K & S:1027I are shared with other variants of concern.

Notably, the cluster in South Korea does not have additional Spike mutations, suggesting this also may not be spreading due to viral change.

8/8 ImageImage

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More from @firefoxx66

16 Jul
The underlying problem isn't that the UK COVID-19 app is 'too sensitive.'

With a quarter-million cases & few restrictions, even if only correct contacts were pinged, that would be a huge number of alerts & isolations!

And yes - that's going to cause a lot of disruption 🤷🏻‍♀️

1/5
We're papering over the consequences of huge case numbers with debates around sensitivity.

Yes, we can turn sensitivity down - but # of alerts will continue to grow with cases - still potentially annoying people (who uninstall) & certainly continuing to cause disruption.

2/5
This isn't to say we shouldn't try to make pings more accurate, rather, that this isn't an actual solution to high number of pings right now.

Even if 30% pings were bad & we could get perfection now, UK cases rose 33% this week - so we are still at crazy high notifications.

3/5
Read 5 tweets
7 Jul
🎉CoVariants.org update! 🎉

4 new variants & focal builds added:
- 21G (Lambda) (C.37)
- 21H (B.1.621)
- 20B/S:732A (B.1.1.519)
- 20A/S:126A (B.1.621)

Also - we have awesome new flags on the Per Country page! 🏁🚩

Let's take a closer look...👀

1/10
21G (Lambda) was recently classified a VoI by @WHO & included in @nextstrain builds. It seems to originate in South America - we can see its prevalence in countries like Chile, Argentina, Ecuador, & Peru (purple-pink):

2/10
Looking at the focal build, we can see that 21G (Lambda) has also been found in North America, Europe, the Middle East, and Australia.

Lambda has a unique 7 AA deletion in Spike, & a mutation at S:L452Q.

3/10

nextstrain.org/groups/neherla…
Read 10 tweets
24 Jun
Another brief update: many of the latest focal builds are still baking🥖, but I've gone ahead and pushed up some finished Delta-related runs.

In particular, I wanted to look a little at what's being called 'Delta Plus' = Delta + S:417N mutation

1/9

nextstrain.org/groups/neherla…
S:417N has actually popped up multiple times in the Delta variant - it's of interest because it's thought to be related to immune escape & is also found in Beta.

But looking below, there are 2 main clusters - @PangoNetwork lineages AY.2 & AY.1

2/9

nextstrain.org/groups/neherla…
I don't have 1 build that shows these clusters perfectly yet (working on it!), so we'll use 2 - the focal builds for Delta & S:K417.

Delta: nextstrain.org/groups/neherla…
S:K417: nextstrain.org/groups/neherla…

3/9
Read 9 tweets
24 Jun
🛠️CoVariants.org Update!🛠️

The latest push to CoVariants tweaks how sequences are classified as Variants in some cases, & you'll notice changes in some graphs as a result.

Overall, this change means better classification for lower-quality sequences👍🏻👏🏻

Read on...

1/6
CoVariants looks at nucleotide changes to classify sequences - a sequence must have all of a list of changes to be classified.🧬🔢✅

But sometimes during a sequencing, part of the DNA might not be 'read' ("low coverage"), so we have no information for some locations. ❓

2/6
If some of the positions CoVariants is looking for have low coverage & no information, they won't get classified as Variants. 🧬1⃣2⃣4⃣✖️

This can particularly impact places sequencing lower-quality sequences, as CoV will 'undercount' how many are variants! 📉

3/6
Read 6 tweets
21 Jun
🎉.@WHO and @nextstrain names come to CoVariants.org!🎉

Now it's easier than ever to identify the variant you're interested in - and with beautiful new badges! 🔍

Also, the date plotting on the Per Country page has been made clearer!📈

Let's take a look... 👀

1/4
CoVariants now uses the same clades (including WHO names) you see on Nextstrain.org, making it easy to find a variant of interest!

This comes with beautiful new variant badges - & an updated Name Table that includes Pango & WHO badges, & old CoVariants names! 🎨🌈4

2/4 Image
Of course, this carries over to the Per Country page, where the variant order is also more intuitive. 📜

Additionally, the date axes have been made clearer with more lines, & mouse-over now shows exactly what period the data comes from! 🗓️

3/4 ImageImage
Read 4 tweets
7 Jun
It's incredibly thrilling to have this paper out at last! 🎉

"Spread of a #SARSCoV2 variant through Europe in the summer of 2020"

(aka The Tale of Europe, Summer Travel, & EU1)

But why should we care about summer 2020 now? Let's take a look...

nature.com/articles/s4158…

1/24
Last Sept, while looking for #SARSCoV2 sequences that could help us understand transmission across #Switzerland, I noticed a cluster that was present not just across Switzerland, but also the UK & Spain. This is the cluster that eventually came to be known as 20E (EU1).

2/24
EU1 had a mutation at position 222 in spike - this caught my eye.

From mid-summer 2020, EU1 (orange) expanded across Europe - becoming the most prevalent variant in most of Western Europe, & accounting for >30% of sequences in Europe by the end of 2020.

3/24
Read 24 tweets

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