I moved to New York City in 1988 as the AIDS crisis was entering its darkest chapter. In the West Village, it could be seen on the faces of passersby, not just faces that were gaunt and wasted from the disease, but faces full of worry, grief and despair. At lunchtime, I would dutifully read the obituary pages and note the terribly young ages of the dead, as if one might gather up all that lost time, all that life unlived and preserve it for later use, like holding onto something a forgetful guest leaves behind.

When my own fears were overwhelming, I would walk across town to the bookstores of the East Village — the Strand or St. Mark’s — where I hoped to find something that would offer a little mental equipoise. There was one book that changed me forever, a book that felt like the intellectual equivalent of taking 10 deep breaths during a panic attack. It was a slim volume called “Illness as Metaphor,” by Susan Sontag. First published in the New York Review of Books in 1978 and ’79, the extended essay on how society frames illness was written after Sontag’s struggle with Stage 4 breast cancer in 1975.

It is as clear, passionate and convincing a polemic as anything any critic has ever written, and it makes a simple argument with great subtly: that we should treat illness as illness, and not encumber it with images, metaphors and moral valuations. Cancer is cancer, no matter what society whispers in your ear about the disease, why you got it and how it will affect your body.

“I want to describe not what it is really like to emigrate to the kingdom of the ill and live there, but the punitive and sentimental fantasies concocted about that situation,” Sontag wrote. Because we are all mortal, she argued, we will all suffer illness, but we don’t need to carry a lot of social baggage on that journey. By learning how metaphors structure our experience of illness, we can diminish their power over us.

Now we are sick again, vastly sick, across all seven continents, with millions dead from a pandemic that has raged for more than a year. The end of this sickness is still uncertain and many months away, especially for those who live in the poorest parts of the planet. Is it possible, at this point in media res, to discern and maybe take some control over the metaphors and images that structure our social sense of covid-19? Perhaps there hasn’t been enough time, and the coronavirus moves quickly and is now mutating, so its metaphors may change, too.

But there is one idea that recurs in discussions of the disease, and is essential to understanding how it operates and bears some of the dark fantasies and imagery that Sontag warned against: Covid-19 is a disease of inflammation, a medical term, but with its Latin roots in the idea of kindling or setting something on fire. The word inflammation was an essential one to early accounts of the virus coming out China a year ago.

“Poorer outcomes in older people may be due in part to the age-related weakening of the immune system and increased inflammation that could promote viral replication and more prolonged responses to inflammation, causing lasting damage to the heart, brain, and other organs,” reported a doctor at Jinyintan Hospital in Wuhan in March. Among the disturbing reports of an illness that was supposed to be like the flu, attacking our lungs and making us cough, were weird accounts of young people, including athletes, whose heart tissue was inflamed and stayed that way for weeks or months.

But inflammation isn’t just an actual symptom of the disease. It seems to be part of its etiology, its moral and social origins and effects. Covid makes bad things worse; it inflames things. An article in the Asian Financial Review in March 2020 described it with an odd image: “It is rather like a dangerous, unwanted guest at a dinner party.” And what did this guest do? It created a kind of panic in the immune system, putting it into overdrive: “Rather than helping the stressed lungs, it induces too much inflammation, making the situation worse.”

Scientists used the word “comorbidities,” but lay people understood things more simply: If you are not in good health, this virus will make things worse. Social scientists and critics borrowed the image, too, noting how covid inflamed preexisting social tensions and inequities. It disproportionately attacked the poor and people who have historically been marginalized, including people of color.

Throughout the summer, as Americans took to the streets to protest the police killing of George Floyd in Minneapolis, the sense of inflammation only grew. Covid was diabolically crafted to afflict a world in which we were already raw, sore and constantly rubbing up against other, generating friction as we circulated both globally and locally. It was a cosmopolitan disease — an unwanted guest at a dinner party — but a cosmopolitan disease that was killing the front-line workers who keep the incessant churn of our economy in motion.

Its origins seemed to lie in a leap from the animal kingdom to the human body, a transmission aided, perhaps, by unnatural proximity and even global warming, as humans push farther into territory that was once sparsely or mostly uninhabited.

“Global warming will make diseases more prevalent,” an expert on pandemics and the travel industry told the Boston Globe earlier this year. “It’s humans encroaching on natural habitats, which makes zoonotic diseases even more prevalent.” Air pollution, warned a group of top cardiological health organizations, also was exacerbating the risk of covid deaths.

In “Illness as Metaphor,” Sontag wrote about diseases — cancer and tuberculosis — that took their toll over relatively long periods, so the experience of being ill lasted months or years. Covid, however, moved fast, burning through its victims not like the slow consumption of TB or the inner dissolution of cancer, but like a rapidly moving fire. The metaphor of “wildfire” became common in descriptions of the disease, especially “flare-ups” as countries that initially brought down their infection rates faced sudden surges of infection. Wildfire seemed a more apt description of the disease than the straightforward scientific discussion of a virus and its vectors, perhaps because “virus” was already in use to describe the disinformation that enabled covid to scorch the Earth.

Sontag’s book, and a later essay she wrote about AIDS and its metaphors, allowed me to step back from my own fears, and see things a bit more dispassionately. She scoured literature, art, philosophy and psychology to describe how society often attaches a moral dimension to illness. The ancient world looked at disease, especially plagues, as evidence of divine wrath. In the 19th century, TB inspired a more subtle moralism: This disease revealed character and seemed to refine and even ennoble souls.

With cancer, and later AIDS, the punitive fantasies returned. Cancer, Sontag wrote, was “a demonic pregnancy,” a disease of wealth and abundance, even, perhaps, a disease of thwarted desire and stymied libido. “The dying tubercular is pictured as made more beautiful and more soulful,” she wrote, whereas “the person dying of cancer is portrayed as robbed of all capacities of self-transcendence, humiliated by fear and agony.”

With covid-19, we don’t know quite yet what to do when it comes to blame. President Donald Trump made repeated efforts to brand it as “the China virus,” and it’s fascinating that this shameless and xenophobic label never gained traction with most Americans. People seem intuitively to understand that the virus doesn’t respect identity or nationality, that it is a symptom of a larger, transnational condition. But beyond that basic intuition, there is little agreement about the moral dimensions of the disease. And that lack of agreement only inflames things all the worse.

The moment Trump framed the disease as something you either believed in, or didn’t, we spiraled further into the flames. Trump’s handling of the pandemic may have destroyed his credibility, but the virus inspired the apotheosis of Trumpism. It was like an accelerant on the embers of anti-Enlightenment thinking, encouraging a basic skepticism of science, even distrust of elemental structures of thought, such as cause and effect. Those who refused to wear masks and take other basic precautions sometimes cited pseudoscience, but often, they were simply fatalistic. Perhaps they wouldn’t get the virus, perhaps they would, who really knows anything?

The rest of America was bewildered by this. We have to varying degrees absorbed the fundamental lesson of Sontag’s book — that we must disconnect ideas about illness from moralism — so it was hard to know what to do when covid tested our national, moral character. The world is sick, and getting sicker, because so many people seem not to care at all about the well-being of others. Having lived through an age in which scoundrels and bigots argued that AIDS was divine retribution, I have no stomach for attaching moral sentiments to this illness. I may be angry at incompetent political leadership, but when I see people gathered without masks in restaurants or bars, or in pools or at the beach, it is easier just to be fatalistic. I don’t want to hate these people, so best to direct the anger at everyone, collectively: “We are all doomed.”

Years after Sontag published “Illness as Metaphor,” her son, David Rieff, wrote about how his mother never reconciled with death, how the fear of death haunted her throughout her life. I was, at first, deeply disappointed to read this, because her wisdom had lessened my own fear of death at a critical moment. But I can’t blame her. She reasoned her way as far she could, and beyond that, reason could not take her. There is always a black hole.

Which is where we are now. Some large part of America feels helpless before forces they don’t understand, while the rest of us feel helpless before people we don’t understand. We cannot think our way out of this impasse. We are in the fiery furnace of social disintegration and hope for only one thing: that a super-chilled vaccine cools everything off before we are consumed by it all.