I’m trying to formulate a response to, what at least in my circle of friends and acquaintances, is an increasing insistence that people had Covid-19 in November 2019.
If we assume someone did have Covid-19 in upstate NY for instance what else would have to be true?
I think mainly, that a novel virus made its way around the world without detection would be pretty major. And then it mutated in Wuhan, China unleashing this second, more virulent strain, meaning that the pattern of outbreak that we all witnessed beginning in Wuhan was some kind of ‘second phase’ and not the initial outbreak. It would also mean that current genetic tracing is probably wrong or not accounting for this alleged mutation.
All of this seems very unlikely to me. I don’t think I can prove with 100% certainty it is impossible. Even if I could I struggle to understand the emotional attachment people have to the claim that the illness they had was covid-19.
Unknown respiratory disease = Covid-19 strikes me as about as accurate as UFO = Aliens. But people seem to take it very personally when you tell them they could not possibly have had this illness 2months before the outbreak in Wuhan.
TL;DR: No. The earliest I’d buy for pandemic-track COVID is early-to-mid December, and in China or maybe Australia. Otherwise, it’d have to be a non-pandemic substrain that died out early, and left no children behind except the first Wuhan strain. The theory loses in an Occam’s Razor fight with “your friends probably had something else back then.”
ETA: This post mentions a second independent line of evidence on the matter (using antibodies), and also dates the first COVID-19 cases to no earlier than December.
I’m going to be basing most of this on nextstrain’s COVID-19 phylogeny data and their accompanying chart.*
The earliest sequenced US case we have came from Washington. The Washington strain’s earliest sequenced sample was 5 weeks of mutation out from the Wuhan strain at the time, leading to the inference that it arrived (or at least split off from the Wuhan gene-pool) in about mid-January. Australia seems to have a divergent strain that might have broken off even earlier, possibly as far back as mid-December.
Going on their graph, they dated the Wuhan last common-ancestor (LCA) strain to roughly mid-December, and the all-strain LCA is the same one.
(I’m not going to detail all of how this works, but LUCA is a similar concept.)
So, cases much earlier than mid-December (and in anyplace other than China or Australia) seem really unlikely to me**.
*Note that old phylogenies are often very inaccurate and rough, and rely heavily on your starting assumptions (I’ve played around with them, and it is wild how different the trees can be). But this is a fresh phylogeny, and should be a bit of a best-case-scenario. This a very recent series of mutations and splits, and on top of that, unlike with paleontology we can access, date, and sequence old blood samples just fine. I expect this phylogeny to get the occasional detail wrong, but to hit the broad-strokes and to be largely pretty accurate.
**If an earlier strain existed, it would have had to have left no lingering sequenced sub-strains in the present day. If even one of those theoretical highly-divergent sub-strains persisted, got sequenced, and were added to the phylogeny calculation… it would have introduced a new early-stage split into the phylogenetic tree that would have pushed the probable LCA way back into the past.***
*** I mention this in part because… HIV did have these. A non-pandemic ancestor that we found in some very old blood samples. It was nowhere near as contagious and persistent at the time, and even seemed to be a transient illness for those who caught it. But being a pretty unsuccessful virus at the time, only a very small pool of people had it back then.
Thanks for this, I was not aware of the Bedford lab’s work.
Wondering if you (or any other LW reader) has any thoughts on on the emotional aspect of this.
Seems folks are very attached to the idea that they had Covid-19 earlier than it was identified. It’s starting to get into that ‘can’t be reasoned out of something they haven’t reasoned into’ area.
I’m curious why people are so adamant that an extremely unlikely scenario is actually the most likely explanation. But i guess this cuts across all kinds of mental models and not just covid-19.
I don’t really know, I wouldn’t do this. Here are a couple of possibilities that ran through my mind.
COVID’s symptoms are basically “see: undefined flu-like symptoms.” This might just be an equivalent of “I looked up my symptoms on WebMD and it’s definitely cancer,” only with COVID.
There was that revelation that Washington got it earlier than expected. Maybe they’re pattern-matching blindly to this. It’s really easy to do so, especially if there was another nasty flu or cold going around back then (which there probably was).
People want an excuse to go about their life as normal (or to complain if they’re not)
People especially hate taking the possibility of their own death seriously
Nobody wants to deal with the guilt of knowing that their “normal” actions may be endangering others (cough asymptomatic transmission), and they would rather believe something potentially-false than contend with that
It’s probably a mix of all three, or even more.
With all due affection, I’ve heard that New Yorkers as a whole are fairly prone to contrarianism. So the frequency with which you’re hearing this might also partially be local variance.