Don’t judge Covid conditions by the current rate of Covid growth

These days when I go to Twitter I see so many claims that current caseload or hospitalization numbers (in some not all regions) are approaching their peaks from the third wave last winter.

But don’t be misled by that rhetoric — speed of growth is not at this stage of the pandemic a good metric for evaluation.  Obviously, speedy Covid growth is bad news compared to having no Covid at all, but relative to actual constraints inference here is difficult.  Even the growth of hospitalizations, much less the growth in cases, is a misleading signal for how well we are doing.

First, there is a diehard core of individuals who just won’t get vaccinated.  That is highly unfortunate, but possibly it is better if those individuals get Covid sooner rather than later, at least provided they are not so numerous as to overwhelm the hospital system all at once.  The Covid case is in essence their preferred form of vaccination.  Stupid, yes, but later is not necessarily better.

A second possibility is that we will see waves of Delta Covid, rising rapidly and then declining rapidly.  That seemed to happen in the most badly afflicted parts of India, and maybe has been happening in England and the Netherlands, noting that the English numbers have begun a recent (minor?) uptick again, so we cannot be sure of the dynamics.  The general point stands that it is better to get a given amount of Covid over with more quickly rather than less quickly, again subject to the constraint that you do not overwhelm your hospital system.  Circa August 2021, we are no longer in the older position of “waiting for the vaccines to arrive.”

A third possibility is that Delta really is extremely contagious and that non-pharmaceutical interventions just aren’t going to succeed in checking it.  (Oddly, few elites are willing to mention this possibility.  Though they are willing to tell us how terrible it is, which it is!)  Yes, boosters may help out, but most of the “cavalry” — vaccines in this case — already has arrived, at least for those willing to take them.  OK, so if most people are going to be hit by this thing, and vaccinations do make that event much safer than before, again you want to get that process over with more quickly rather than less quickly.  And to the extent vaccine protection decays (an unknown variable but a real worry), speed really is of the essence here.  Again, all subject to the “don’t overwhelm your hospital system” caveat.

Clearly there are scenarios where the rapid case growth is a bad thing, even taking relevant constraints into account.  For instance, vaccinating younger individuals might be a relevant “cavalry” still to arrive, and maybe it can arrive before most of our young people are exposed to Covid.  Or maybe most of the unvaccinated are pretty “elastic” in their status, and a high but not too high case and hospitalization growth will scare them enough to bring them over to the vaccinated side of the ledger.  Those really are possibilities.

But rapid growth per se — even on the hospitalization side of the ledger — has to be used with care as an indicator of where we stand.  Generating a lot of Covid cases and hospitalizations in a short period of time is a very tricky signal, again relative to the constraints we face.  You need to define your counterfactual very carefully, and recognize that the mood affiliations you were promoting earlier in the pandemic may or may not make sense now.


Comments for this post are closed