Marzio Toniolo / Reuters

You are reading this because of your ancestors’ immune system. The odds of your predecessors surviving the myriad microbes that have stalked humanity every step of its march toward becoming Earth’s dominant species were incalculably long. More Homo sapiens have probably died from infectious disease than all other causes combined. Only in the past 150 years, owing to nutritional and medical advances, have we emerged from living in constant worry that a cough or fever or scrape might be a death sentence. But that fear of infectious disease remains embedded in the brain, as visceral as our sudden alarm when encountering a snake in the wild. Despite all our medical and technological breakthroughs, when confronted by the prospect of an epidemic, we are not that different from a farmer in an ancient Sumerian settlement making offerings to a local fertility deity so that he might survive the mysterious pustules killing everyone in town.

Or so it seemed to me when I was living in Hong Kong at the height of the SARS outbreak, a crisis I covered as the editor of Time Asia, Time’s sister publication. SARS, a coronavirus, emerged in Shenzhen late in 2002 before burning through humanity, eventually infecting more than 8,000 and killing 800 for a mortality rate of about 10 percent. I wrote a book about SARS, and as I read the coverage of the latest coronavirus to achieve widespread human-to-human transmission, which causes the disease called COVID-19, I have noticed a pattern in how the media, governments, and public-health systems respond to infectious-disease outbreaks. There are four stages of epidemic grief: denial, panic, fear, and if all goes well, rational response.

Whenever a new microbial killer emerges, we go through each of these stages, starting with denial as government officials insist that there is no outbreak. When smallpox appeared in the Roman Empire in a.d. 189, one local prefect attributed the upsurge in deaths to a displeased Jupiter, while another assigned blame to a poisoned barrel of wine. In China, where the state largely controls the media, denial usually takes the form of a cover-up. The first mention in the press of the disease that would come to be known as SARS was a story on January 3, 2003, in the Heyuan Daily, a Communist Party–controlled newspaper in southern China. “There is no epidemic in Heyuan,” assured the anonymous reporter on the front page. “There is no need for people to panic.” Just in case readers weren’t convinced, a nameless party official proclaimed, “People don’t need to panic and there is no need to buy preventive drugs.”

Not surprisingly, denial did little to reassure the population of Heyuan, a city of nearly 3 million, who emptied pharmacies of antibiotics and began the widespread boiling of vinegar, a traditional folk remedy for respiratory ailments. Thus denial led to panic. Denial always leads to panic.

“People were overcome with delusions,” wrote Daniel Defoe in A Journal of the Plague Year, a fictionalized account of 1665, when bubonic plague struck London. “All their predictions run upon a most dreadful plague, which should lay the whole City, and even the Kingdom waste.” During the SARS outbreak, I recall going into a local Wellcome, one of Hong Kong’s larger supermarket chains, to find the shelves stripped bare of toilet paper, ramen noodles, cooking oil, chili paste, canned soups, and, of course, rice. (For some reason, Count Chocula had survived the run on groceries and was in plentiful stock.) By way of explanation, one shopper pushing a cart filled with bottled water insisted that Hong Kong had been declared an “infected port.” I took out my phone to call my office and saw an emergency text message from my mobile service provider saying that Hong Kong had not been quarantined or declared an “infected port.” City officials had closed the schools and a 14-year-old had made use of his free time by posting a fake news story under the logo of a Chinese-language newspaper.

With an outbreak like COVID-19, everything from the source, to the means of transmission, to recovery rates remains essentially unknown. So each new piece of information—even data that should be reassuring, like the downward revision of mortality rates—elicits more panic. Frequently, one particular cluster of infection captures the imagination and becomes a symbol for the whole outbreak. During SARS it was Amoy Gardens, a sprawling public-housing complex in Kowloon visible from my offices across Victoria Harbor, where the virus spread via fecal particles that wafted into apartments because of dried-out U-traps in drainage systems. With COVID-19, it is the Diamond Princess, the cruise ship linked to 700 infections after thousands of passengers were quarantined on board, like a leper colony with buffet dining and a Love Boat–themed disco deck party. Accounts like this, of urban or shipborne squalor, fuel our darkest visions.

“A pestilence isn’t a thing made to man’s measure,” Albert Camus observed in The Plague. “Therefore we tell ourselves that pestilence is a mere bogey of the mind, a bad dream that will pass away.” Panic is exhausting. Only so many witches can be tossed into wells or rolls of toilet paper hoarded before knee-jerk anxiety progresses to a steady state of fear. Cities go dark, governments quarantine exposed populations, institutions begin shutting down, and, as we have seen with the erratic stock market, economies sputter. A population huddled indoors can’t till the fields or man the pin factories. “Oxen, asses, sheep, goats, pigs, and chickens and even dogs . . . were driven away and allowed to roam freely through the fields,” Giovanni Boccaccio wrote in the Decameron. “The crops lay abandoned.”

According to Cirium, an aviation-industry consulting firm, more than 200,000 flights in and out of China have been canceled, a 60 percent decline. In 2003, in the midst of SARS, global air travel was down 25 percent. Planes flew into Chek Lap Kok, Hong Kong’s international airport, completely empty of passengers. Hong Kong, a city renowned for its shopping, became a retail ghost town. The eighth-of-a-mile walk from one Prada boutique in Hong Kong’s Admiralty district to another Prada boutique in Central, usually a 30-minute journey due to all the jukes and spin moves required to avoid the throngs of mainland shoppers, was now a five-minute straight shot.

Concerned about the health of my staff at Time Asia, I consulted other managers at various subsidiaries of what was then the Time Warner empire. The local boss of CNN was in New York with his family and would be staying there for the duration of the outbreak. The head of Turner Entertainment Asia hadn’t made any plans, but was eager to hear what I had in mind. “Nothing was more fatal,” Defoe had warned, “then the supine negligence of the people themselves.” Determined not to repeat the folly of Defoe’s Londoners, I did what managers everywhere do when they want to look like they know what they are doing: I convened a meeting. But when I suggested that anyone who had been in contact with a possible SARS case should stay away from the office, it became clear that everyone in the room already knew someone who might be infected. In fact, our circulation manager had dined the evening before at her father-in-law’s apartment at Amoy Gardens. There was really nothing we could do, I realized, besides shutting down our publication. But that wasn’t an option: We were a newsmagazine, and this was news.

Fear dissipates eventually, replaced by a more realistic sense of the risks. An epidemic, even one of a disease as seemingly easy to transmit as COVID-19, while burdening public-health systems and potentially deadly for the elderly and those with compromised immune systems, is eminently survivable by the majority of the population. This fact becomes obvious as people become sick, yet recover; doctors and nurses get a better handle on treatment; and most people go about their life and never succumb. In some ways we were lucky at Time Asia, because we had no choice but to continue visiting hospitals, talking with doctors, and interviewing virologists. We were worried, yes, but proximity to the professionals gave us clarity about the actual risks we were facing.

Which brings us to the last stage of epidemic grief: rational response. After denial, panic, and fear, we can finally get down to the business of basic sanitary measures and infection protocols. At Time Asia, we urged better hygiene. We reminded anyone with a fever to stay home. We looked on as the medical establishment formalized the clinical response, determined diagnostic criteria, and isolated the virus.

Guan Yi, a University of Hong Kong virologist who was among the first to figure out the animal vectors for SARS, once told me there are only four things you need to know about a virus: “What is it? What does it do? Where does it come from? And how do you kill it?” We were nearly two months into the SARS outbreak before Guan’s colleague, the fellow virologist Malik Peiris, identified the virus that caused the disease. By then, clinicians had a good idea of what it did. Guan Yi was the scientist who figured out where it had come from—southern China’s wild-animal markets, where bats and civet cats were sold and slaughtered. So what killed it?

We never did develop a vaccine. With SARS, infections peaked sometime in May 2003, at about 9,000 cases. By then, the daily rate of new infections had dipped below the number declared cured or dead. That is the inflection point of any outbreak, the point at which the worst is over. Why did the rate of transmission slow? Part of the answer is seasonality: The Northern Hemisphere’s virus season tends to run from winter to mid-spring, perhaps because people aren’t clustered indoors and so are less contagious, or because viruses might weaken in lower relative humidity or direct sunlight. (Nobody actually knows.) In the case of SARS, the battle was won one hospital ward at a time. In the antibiotic era, infection control has been largely delegated to IV drips rather than sanitary cordons. With respiratory diseases like SARS, MERS, and COVID-19, 19th-century medical techniques and equipment—masks, gloves, galoshes, sealed wards, quarantines, and ventilation—are what comprise a rational response.

If you want to panic, go right ahead. It’s what we do. It’s what your ancestors did. Then be afraid. Eventually, however, roll up your sleeves and get to work, scrubbing this bug back to whatever its host species happens to be. We’ll get there. Humanity has so far survived every microbe that has jumped the species barrier, and we will survive this one.

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