The classic comparison is, of course, to pandemic strains of influenza. The flu is characteristically seasonal, with transmission rates dropping in summer, rising in fall- for reasons less clear than they might seem. The obvious explanation is that the flu virus hates the heat or sunlight- but why then are tropical countries subject to flu outbreaks at all?
In any event, when the flu occurs in waves, they are waves of transmission mediated by the virus. In a human population behaving much the same at times A, B, and C, the flu might circulate briskly at time A; not circulate at time B; and then circulate briskly again at time C. Time C in this scenario…is a second wave.
But that is not at all what is happening with COVID-19.
Thus far, the virus has circulated quite consistently- including now, in the middle of our (northern hemisphere) summer. Any notion that SARS-CoV-2 would take the summer off to return in the fall is obsolete. This virus, in an apparent departure from influenza, is clearly willing and able to work steadily through the summer.
What accounts for changes in COVID-19 transmission- by location, and over time in a given location- seems to owe just about nothing thus far to any vagaries of the virus. The fault, as it were, lies not in SARS, but in ourselves. Our behavioral changes readily account for changes in transmission.
Where we locked down before the virus was already widespread, we stifled transmission. But this was never anything remotely like a “cure,” nor the full measure of managerial success the most ardent champions of “flatten the curve” may have inferred. This was much more like a levee tossed up in haste to contain a flood. Every person who stayed hidden from the virus played the part of a sandbag. At no point thus far, however, have the floodwaters receded.
Accordingly, the moment we started pulling sandbags out of that human “levee,” the flood was there to be unleashed. This was not a “second” wave, not a new inundation; this was and is the contained first wave, waiting to wash over us in whatever way we allowed it - as was perfectly predicted in the early days of the pandemic, seemingly now several lifetimes ago.
Where no such levee was constructed in the first place- notably, Sweden- the flood of contagion crested, and has mostly dissipated. If there were a sudden, new spike in cases among the general population in Sweden, it would be our first glimpse of a genuine “second wave,” and we would need to account for it. Potential explanations could include environmental changes favoring more concentrated exposures to the virus, or mutations of the virus itself. But to date, we have no need for such explanations for a second wave that has yet to occur. The situation is much the same in northern Italy, and in New York City- both of which locked down only after the virus was too widespread to contain. What Sweden did by design, these locations did inadvertently.
There is no second wave- thus far, at least. Surging case counts in much of the United States and many parts of the world are exactly what we should expect when a formerly unexposed population comes indiscriminately out of lockdown while the virus is still circulating. This is the viral analogue to pulling down our levee before the flood waters have receded.
Yet, reports from all over the world refer to a second wave that will muddy understanding of these floodwaters of contagion. Even as we live through this indelible patch of history, we are laying down tracks to misremember it. As our experiences make history, our accounts of the experiences mismake it. If current indications are reliable, much of what we record about this pandemic will be gibberish.
I can’t help but wonder: how much of what has been recorded for past pandemics, informing our understanding of this one, is gibberish, too? Famously, those who don’t learn from the follies of history are destined to repeat them- but how much is that compounded when the lessons of history are themselves folly? I shudder to think.
So much for ruminations on a misrepresented present translating into a misrecorded past. The pandemic itself has been clear and consistent in its behavior, providing guidance through the lens of epidemiology that the conflicting views of ideology conspire to obscure. Where are we now, and what does that portend for what will, and should, happen next?
Those many parts of the U.S., and world, that locked down initially and then opened up haphazardly to unleash the pent-up first wave are prone to one of several scenarios now: they can (1) lock down again and if they do, they can do it either (a) before, or (b) after, the virus is already widespread; or they can (2) ride it out. In either scenario 1 or 2, the response can be of the prevailing “one size fits all” variety, or it could be matched to risk tier. In other words, those at high risk of severe COVID outcomes could return to lockdown, while those at low risk ride it out.
If any given location locks down before the virus is widespread, they are back where they were before- crouching behind that levee. If they lock down too late to prevent widespread transmission, they will be like New York City, or northern Italy. The toll will be unnecessarily high, because the highly vulnerable will be exposed along with the rest. So, too, if they ride it out without meticulous protection of the most vulnerable.
If any approach is taken -intentionally, or otherwise- allowing for widespread viral transmission, then, as in New York City, the wave of contagion will apparently dissipate in a number of weeks. Accordingly, those sites currently subject to a “delayed first wave” will likely be through it and watching it recede in 6-8 weeks, give or take.
To reiterate, we have no evidence to date of a “second wave.” A sudden “return” of this virus in the fall seems obviated by its continuous activity now, during the summer. We cannot know, of course, but it seems to me we can be hopeful that this contagion is the single, great inundation it has shown itself to be- before it recedes into the background noise of infectious disease epidemiology.
There are more and more very encouraging indications of widespread, native resistance to this virus - to one degree or another. Recent studies suggest case counts an order of magnitude higher than documented to date (i.e., not 4 million cases in the United States, but 40 million), the vast majority of them asymptomatic or too mild to note. Others highlight the probability that as many as half of those exposed to COVID-19 don’t get infected at all, owing to partial immunity conferred by prior coronavirus exposures.
Such indications were present in the global patterns all along. They do not suggest a complete or perfect immunity- they imply a partial resistance that makes infection less severe, and less likely, with “average” exposures. Reports of severe disease in young, healthy health professionals likely indicate how such partial resistance may be overcome with intense exposure- which in turn argues for the utility of masks and distancing to minimize the viral exposure doses most of us encounter.
The combination of enormous numbers of undocumented, asymptomatic cases; of a high percentage of the exposed remaining uninfected; of rising prevalence of detectable immunity; and of some immunity achieved in ways our lab tests do not routinely measure (i.e., reactive T cells and secretory IgA, without production of IgM or IgG, for those concerned with such particulars)- seemingly put us monumentally closer to herd immunity than we have acknowledged. If this data aggregation is what it seems, we are weeks away from this pandemic being all but over- and we will have the relative protection of herd immunity (except in any parts of the world that stay in strict lock down) long before the advent of a vaccine.
Less speculative than the end of the pandemic is the accounting of its toll among us to date. We now have a monumental and indisputable volume of data from all around the world confirming what the earliest views of the pandemic suggested: there are massive risk differentials associated with COVID19. The elderly and frail are at extreme risk, especially the residents of long-term care facilities; the elderly but hale are at elevated risk; the chronically ill but not elderly are at elevated risk; the young and healthy are at low risk, very low risk, or- when under 30, in good health, and not subject to extreme exposures- even vanishingly remote risk.
But let’s be clear: any level of risk is more than zero. With a sufficiently high exposure dose, even young healthy immune systems can be overwhelmed. We must guard against distorted thinking about risk. For the “all clear” to sound, we do not need there to be zero risk related to COVID; we simply need COVID-specific risks to fall at or below the level of other risks we willingly encounter in our daily routines. None of us has ever lived through a day with a zero risk of injury or death. All that is required to be at non-zero risk of dying today, is living today; the pandemic does not alter that inalienable fact.
We have no reliable basis to predict total COVID mortality, and never did. This is not because we are ignorant about this virus, although of course we are, still climbing the steep part of the learning curve. Rather, this is because our policies may change with mortality predictions, and those policies may in turn cause actual mortality figures to change. In other words, a sanguine prediction about fatalities may invite cavalier policies, which in turn- allow far greater fatality rates. In a tragic twist, these are self-unfulfilling prophecies.
We also cannot yet say what the mortality toll of the pandemic will prove to be, and won’t know for as long as several years. Why? Because in the United States, without a pandemic, about 8,000 people die of miscellaneous causes daily. Those deaths are, of course, highly (but not fully) concentrated among the old and sick, exactly as COVID deaths are. What, then, is the overlap? To what extent is the pandemic adding to total deaths in a given year, and to what extent is it shifting the cause of death but not the toll? No one can say yet, and only time will change that.
In children, the fatality risk from COVID-19 is less than that associated with the commute to school by car or bus. We could have reopened schools had we not bungled the reopening overall. But we have, and schools really cannot be opened anywhere viral transmission is uncontrolled. However, if the U.S. is now destined to “ride out the wave” it inadvertently released upon itself, transmission rates are apt to be low and falling in 6-8 weeks, suggesting that schools could be opened safely soon- just not quite at the customary time.
We have missed much, but perhaps not yet every, opportunity to minimize the total harms of this pandemic by means of risk-stratified interdiction. As the virus circulates widely, complete lockdowns that come in time will obligate populations to crouch behind that levee, waiting for relief in the form of a vaccine; while those that come too late will simply add the insults of lockdown to the unfettered injuries of the virus. There are, clearly, locations that suffered the worst of both, the very antithesis of total harm minimization.
The alternative to such unappealing options is to choreograph waves of our own: waves of return to something like normalcy, sequenced in accord with our personal risk. A rise in case counts is unimportant if cases are mild; a concomitant rise in hospitalizations means we are failing to protect those who cannot be exposed. We know more than enough to distinguish these populations- but to date, have implemented almost no policy choreography predicated on this crucial intelligence.
Finally, there is the one, true opportunity in this crisis- the chance to advance the state of health for the population at large. Risk for bad COVID outcomes is related to age we cannot change, and personal health status we generally can. The impact on acute COVID risk of personal health improvement by means of diet and lifestyle can be very substantial, while the long-term contributions of lifestyle as medicine to years in life and life in years are apt to be at least as great. Getting healthy during the pandemic is both a robust, acute defense, and a gift that keeps on giving.
Getting healthy now should be a national priority, a cultural priority, a corporate priority. Absent any such sensible policy, it should be a personal priority. Either way, reduction in COVID risk can begin with one walk displacing the couch, one meal of wholesome foods displacing junk. Benefits accrue and rise over time.
I guess there has been one other “opportunity” in the pandemic: the chance to watch the Broadway smash, Hamilton, live streamed on television. The show is as disquieting as it is riveting. The plot, one part education for every part entertainment, tells us in its uniquely dazzling fashion that even our most iconic history is subject to distortion. So much of what we call “history” is really just… “story,” told by those who controlled the narrative, until someone else did. Much of what we comfortably believe is wrong, to one degree or another.
That disquiet is amplified while living through this stretch of indelible history, watching it be refracted and disfigured through the diverse lenses of ideology even as it plays out around us. Absent a unified devotion to epidemiology ahead of ideology, we seem destined not only to mistake our responses to this pandemic, but to mismake the very history of it. I wonder what we may hope to learn from that level of folly.