Editor's Note: (Kent Sepkowitz is a CNN medical analyst and a physician and infection control expert at Memorial Sloan Kettering Cancer Center in New York. The views expressed in this commentary are his own. View more opinion on CNN.)
(CNN) The unrelenting Covid-19 pandemic is now well into its fourth wave. Although more than half of the United States is fully vaccinated, the wildly contagious Delta variant is causing trouble throughout the country, with some areas seeing more daily infections than ever before.
Though this moment is unsettling, sooner (we hope) or later the Delta variant will pass. It may be difficult to believe, but it's inevitable. The 1918 "Spanish" flu, for which there was no vaccine, infected about a third of the world and eventually fizzled out after three waves, although the virus itself never fully went away: scraps of its genes can be found even in today's influenza strains
What goes up eventually comes down. The B.1.1.7 variant of the virus that causes Covid-19 first identified in the UK and now referred to as the Alpha variant, routed much of the US over the winter before cases dropped back down, in large part due to the vaccine rollout.
Similarly, we should keep in mind that pandemics eventually end, often receding into pockets of disease here and there, either because a society effectively controls it, a vaccine is administered widely enough to hem it in, the virus itself changes into something less threatening, the weather changes or some other mysterious force that seems to govern epidemics comes into play.
Which raises the next question now forming in the minds of scientists and veteran worriers everywhere: what will happen once the Delta variant has finished infecting whomever it will infect? Will the horror show finally end? Or will there be yet another wave of yet another variant, one that can evade the current vaccines? Are we looking at an even worse lockdown than the grim pre-vaccine hunkering that we saw in 2020?
No one knows. I repeat: no one knows. No one can know. Which means even though we might be approaching an awkward start-stop, yes-no, relax-panic, "is it really over?" phase, we are stuck flying blind. Sorry. But regardless of the irreducible uncertainty, we're bound to see articles -- many, many articles, like this one -- and interviews -- many, many interviews -- on what comes after the Delta variant. Even though planning doesn't always make perfect, considering the range of "maybes" is the only way to prepare.
Here is my guess on what's ahead. The Delta variant will continue to overwhelm unvaccinated communities. Right now, Mississippi and Oklahoma, both of which have vaccination rates that are lower than the national average, have unimaginably high rates of test positivity, exceeding 50%; an additional six states have test positivity rates that are higher than 20%. While Florida and Alabama do not release this data to the Johns Hopkins Coronavirus Resource Center, they are also likely to be high in both states, given the rising case numbers there.
And these are the rates before millions of unvaccinated pre-teens are marched off to school, many unmasked and undistanced. This will likely lead to more spread and more soul-crushing tragedy, much of it vaccine-preventable. This surge of new cases, which we saw at the start of the school year in 2020, will take a while to settle down. And by then, we will be looking at the winter -- when the prospect of being stuck indoors hour after hour will feel particularly grim.
But despite all this, I am somewhat optimistic. At this point in the pandemic, 69% of the eligible US population have received at least a single dose of vaccine and within a few months, the Food and Drug Administration (FDA) is likely to approve the current mRNA vaccines for Emergency Use Authorization (EUA) in pre-teens. There are only so many unvaccinated people at this point who can get infected. While breakthrough cases certainly do happen, they remain a small minority of overall cases -- at least for now.
Thus, even with the persistent proliferation of anti-vaccine, anti-mask and anti-distancing messages, states with high vaccine rates did indeed pull themselves out of the sky-is-falling misery of the winter. While there is of course backsliding as the Delta strain takes hold, these states continue a relatively normal existence. Yes, masks are back in many cases, and there are difficult decisions ahead about schools and the need for booster shots.
In contrast, states with low vaccination rates are on a much more difficult path and will not establish equipoise with the virus until thousands and thousands more become ill. The ones that survive, combined with those already vaccinated, will eventually provide a comparable collective immunity that will allow them to establish something resembling normalcy -- though at tremendous cost of life, health and resources.
Of course, this all may fall apart due to a second problem introduced by our disjointed response to the pandemic. By prolonging the time it takes to control the pandemic, we have dramatically increased opportunities for new variants to emerge, including one with a potential doomsday mutation that renders our current crop of vaccinations useless. Though possible, this seems unlikely. Vaccines are not like antibiotics; the latter typically tend to either work or not work at all. Vaccines on the other hand, likely by provoking the many different prongs of the immune system, may lose some edge against new variants but not with the same dramatic off-on suddenness of antibiotics. As studies have shown, the mRNA vaccines remain quite effective, though admittedly less so against the Delta variant.
Plus, the scientific community has long had experience chasing after the genetic contortions of various viruses and bacteria. The genetic composition of influenza is famously shifty, requiring a new vaccine each year that aims at the four likeliest strains. Pneumococcus, the most common bacterial cause of pneumonia, also can change serotypes (similar to strains), making adjustments a necessity. But we have the tools to identify and adjust to these changes relatively quickly.
All of this is, of course, only my educated guess. Covid-19 behaves in ways we've never seen before -- there's the lack of clear seasonality, the transmissibility before clinical illness and the hyperinflammation that causes the bulk of serious clinical illness. With vaccines as with so much else, Covid-19 may not play by the previously established rules.
Uncertainty abounds right now as it has for the entire pandemic. The only real certainty we have is this: the world's herd will eventually become immune to the Delta variant one way (via vaccine) or another (through infection, disease and possible death). Humans can decide between the options but the virus has declared its intent.
As for what the world will look like post-Delta, that too remains uncertain. But Covid-19 looks increasingly like it's here to stay. Much like the seasonal flu, we will probably have coronavirus outbreaks in the years ahead, with good years and bad years and better and worse vaccine boosters. And much like measles, whooping cough and other preventable infections, there will continue to be relatively small groups of people who prefer to forgo vaccines, despite the many risks. This, of course, could then endanger the rest of the population.
Regardless of what the post-Delta world holds, we need to do much better in the here and now. Despite the overwhelming scientific evidence that supports the use of vaccines and other precautionary measures including masks, the demoralizing one-sided debate about their efficacy continues. Meanwhile, more than 621,000 people -- including young children -- have already died and more will die, be it from the Delta variant or whatever comes next.
It appears this debate, fueled largely by misinformation, will continue until the public recognizes that the pandemic is caused by an infectious disease and not political opportunism. Given this simple fact, it will not be stopped by threats or protests or speeches, but rather by vaccination and other preventive measures -- just like so many infectious diseases before it.