Another fantastic preprint on BA.3.2's propensity for children, this time from Yunlong Cao & co.
They not only confirm David Ho's lab findings (that kids have ~0 Ab response to BA.3.2) but dig into the details of exactly why kids are so vulnerable to BA.3.2.
www.biorxiv.org/content/10.6...
1/6
Ryan Hisner
The ongoing evolution of SARS-CoV-2 is heavily constrained by population-level immune imprinting. Recent genomic surveillance reveals an unexpected demographic shift: the highly mutated BA.3.2.2 subli...
This is awesome. Looking forward to see what they find.
So it will be extremely interesting to see if, as these findings seem to suggest, BA.3.2 will eventually acquire RBD mutations that allow it to spread widely in adults, and if BA.3.2 eventually takes hold in China.
Read 🧵 & very readable paper for details.
threadreaderapp.com/thread/20644...
6/6
🧪 Quite a ride with BA.3.2
What we learned:
1/n Highly mutated spike protein. High antibody evasion, reduced ACE2 binding.
bsky.app/profile/ryan...
Two huge takeaways for me:
#1. Big wins for vaccination & mRNA vaccines:
• Kids vaccinated before being infected have robust antibodies against BA.3.2
• Unvaxed adults much more vulnerable to BA.3.2, esp. compared to mRNA-vaxed adults.
2/6
There's still a major paradox here I can't wrap my head around: countries with the highest vaccination rates & the lowest proportion of children appear—very low sequencing makes hard conclusions difficult—to have the highest proportion of BA.3.2.
4/6
bsky.app/profile/ryan...
#2. BA.3.2 may have the potential to acquire RBD muts (esp. FLip—L455F-F456L) that would overcome its vulnerability to type-1 antibodies. This would enable it to infect adults on a wide scale & potentially make a (delayed) global sweep.
Caveat: cell entry/infectivity tests done in Vero cells.
3/6
Furthermore, the results from this preprint suggest BA.3.2 should have great success in China, with its weakly imprinted population. But we've yet to see a single BA.3.2 sequence from China. (Caveat: extremely low sequencing in China of late).
5/6
bsky.app/profile/ryan...
This was one of the most complex projects I have ever been involved in. Took us the better part of a decade, but I thoroughly enjoyed every minute of it. Especially the intensive and extensive interactions with @wsdewitt.github.io, @matsen.bsky.social, and @tylernstarr.bsky.social
Very low circualtion of SC2 in western countries, probably the most interesting tool right now is the @solidevidence.bsky.social WW dashboard per mutation: lung.fish/wastewater-d...
In US RW.1.1 and RF.5 (they are distant but with a somewhat similar spike) seems now expanding, RV.1 & PQ.16.1.1 too
Ryan Hisner
Ryan Hisner
Ryan Hisner
Ryan Hisner
Ryan Hisner
Stefan Pöhlmann
Ryan Hisner
Gabriel Victora
Federico Gueli
I’m so excited. Our secret (not so secret) observational experiment is about to begin.
This is a once in a lifetime opportunity for wastewater surveillance.
FIFA World cup.
1/
@securebio.org
www.scientificamerican.com/article/the-...
@yunlong_cao: Our latest preprint is out, where we investigated a profound SARS-CoV-2 epidemiological anomaly: BA.3.2.2 is selectively infecting children. Here, we show that the lack of ancestral-stra...
As millions of soccer fans pack FIFA World Cup venues, public health scientists created a wastewater monitoring network to forecast potential disease threats—from measles to Ebola
This started in 2019 as daydreamy PhD student musings with Tatsuya Araki. We're as excited as ever about germinal centers as a platform for experimental evolution.
Many thanks to PIs @victora.bsky.social @matsen.bsky.social, co-1st authors Ashni Vora and Tatsuya, and many other key collaborators!
Not everything we see fits into this neat picture though. There seem to me to be a couple paradoxes.
#1. BA.3.2 has been most successful in countries with the highest vaccination rates: the UK, Spain, France, Australia, Japan, South Korea, Israel. Meanwhile... /11
bsky.app/profile/snpo...
...BA.3.2 has struggled badly in countries with lower vaccination rates or which lacked access to the most powerful (mRNA) vaccines: South Africa, South America, China, USA, etc. This doesn't make a whole lot of sense to me. /12
bsky.app/profile/snpo...
Antibody affinity maturation results from a somatic evolutionary process that takes
place in the germinal center. A “parallel replay” experiment on germinal center B
cells reveals the evolutionary for...
The significance of the sequence below is modest, but it raises some questions:
➡️Why has BA.3.2* not been detected in South America until now?
➡️Why are there still no BA.3.2* reports from mainland China?
➡️And why does XFG reach almost 100% dominance in Russia?
#BA32
Stefan Pöhlmann
This sequence from French Guiana 🇬🇫, hCoV-19/French_Guiana/IPG20260024, EPI_ISL_20449452, is the first - and currently the only - BA.3.2 sequence from South America deposited in GISAID. #BA32
