Pre-Existing Immunity

If Americans had previously high immunity against coronaviruses that only gets overwhelmed under extreme conditions, like intense contact (long indoor exposure) or extreme age-related or medical problems, that would both advance and set back the high-volume arguments around the league.  OTOH, if other countries aredemonstrating higher immunity, that would show the opposite, that the deeply desired “herd immunity” might elude us and make us more vulnerable for reinfection.  There would not have been any good way to know that we were more, or less susceptible than other countries when the virus was beginning to threaten us in February, so the high estimates of infection would have been justifiable.  I did see a few predictions that Americans were in a better position for behavioral and cultural reasons – less multigenerational housing, better handwashing and distancing to begin with, better care for the elderly, things like that – but nothing I recall that said “We are at more/ less risk because we have better overall immunity or better coronavirus immunity than other places – including the immigrant populations of Europe.” 

Yet even had we known such a thing was true I don’t know if the recommendations would have been hugely different.  It would still have meant shutting borders and reducing indoor exposure pretty drastically – restaurants, hotels, schools, grocery, retail, offices. Though maybe there wouldn’t have been so much energy and fewer places would have done it.  Great for low-risk places, sucks for high-risk places, if only we knew which was which.

It might provide some explanation for the odd testing results that pop up , suggesting that many more people have been exposed than we think.  Could those be false positives of related diseases (so I guess “partly false” positives), but not a bad thing, because those also provided some immunity? It would also throw off any current estimates what would constitute immunity for an individual, and thus, what would constitute herd immunity. If this is going to turn on widely varying immunities, it’s going to be tough to sort out. I have been thinking of the widely varied questions they ask us when we give blood, highlighting that risk is not just one thing.

It might give all of us increased confidence in terms of reopening, or how we might respond to a reemergence. Or less confidence, but resignation that we will simply be repeatedly hit while other nations get off easier.

Here is a difficulty:  If the natural immune systems of some people knocked C19 or some version of it back without even having to develop antibodies, are they immune from reinfection with higher viral load – or not?  Start watching for the term “Cross-immunity.”  It may turn out to be key.  Or it may just be one of those quaint ideas we floated in late May of 2020.

Competing narratives.  If you are looking for a reason why North Americans might have better immune systems overall than other countries, there is 1) general health, 2) a more diverse population than just about anyone else in the world, 3) travel to more places.  How much do Europeans visit South America? Do Asians visit the Caribbean all that much? African tourism is dependent on…go, on, tell me.  On the other hand, Vietnam and Singapore might have enhanced immune systems against lots of things because, well, they all seem to start in or near China, with its huge population, and they are right next door.  Plus they are in contact with each other a fair bit.  Choose your narrative.  At present we don’t know.

I will note in passing the number of times I silently curse people on threads who leap in to say “This obviously shows how we destroyed entire economies for nothing…,” not noticing the number of times they have already moved the goalposts and likely will continue to do so. Train yourself to keep noticing the extreme words obviously, always, never, destroyed, etc.  These are seldom justified. They are words people use to cut off argument, not encourage it.