One thing that may give pause here though. The competitive advantage of any given variant is a composite of two factors: immune evasion and changes in R0. Immune evasion expands the susceptible pool, increased R0 runs through the susceptible pool faster.
I think it’s possible that BA.2.86 and derivatives have sacrificed some intrinsic infectiousness for greater immune escape. That would explain the relatively low competitive advantage for a variant that’s really quite a large saltation in sequence terms.
That means that while this next wave might build slower than (say) BA.5, it might go on for longer because it will have a larger susceptible pool to chew through before it dies down.
At the moment we only really have enough data to predict the steepness of the rise, not really the level of the peak.
That's fair of course, and I didn't really mention it at all. I deliberately didn't talk about when (and how big) any wave might peak, but that was more about uncertainty about mixing than the factors you mention.
I'm a bit surprised there's not this data on BA.2.86 though - it's been 3.5 months now! - but I haven't really been paying attention to all the biological data because I tend to just keep an eye on the outcomes.
And also note that most of these are BA.2.86 itself and not JN.1, which seems to be more evasive (at least I believe that’s the consensus, as opposed to higher R0)
One thing that may give pause here though. The competitive advantage of any given variant is a composite of two factors: immune evasion and changes in R0. Immune evasion expands the susceptible pool, increased R0 runs through the susceptible pool faster.
I think it’s possible that BA.2.86 and derivatives have sacrificed some intrinsic infectiousness for greater immune escape. That would explain the relatively low competitive advantage for a variant that’s really quite a large saltation in sequence terms.
That means that while this next wave might build slower than (say) BA.5, it might go on for longer because it will have a larger susceptible pool to chew through before it dies down.
At the moment we only really have enough data to predict the steepness of the rise, not really the level of the peak.
That's fair of course, and I didn't really mention it at all. I deliberately didn't talk about when (and how big) any wave might peak, but that was more about uncertainty about mixing than the factors you mention.
I'm a bit surprised there's not this data on BA.2.86 though - it's been 3.5 months now! - but I haven't really been paying attention to all the biological data because I tend to just keep an eye on the outcomes.
There is! Though of course it doesn’t all agree with each other.
https://x.com/longdeserttrain/status/1703509262020878533
https://x.com/yunlong_cao/status/1697318213258981688
https://x.com/benjmurrell/status/1697751445351575656
https://mstdn.science/@richardneher/111035088239391703
https://www.biorxiv.org/content/10.1101/2023.10.01.560365v1
https://www.nature.com/articles/s41586-023-06750-w
https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(23)02397-8/fulltext
And also note that most of these are BA.2.86 itself and not JN.1, which seems to be more evasive (at least I believe that’s the consensus, as opposed to higher R0)