Humanity's greatest predator: A laboratory recreation of the H1N1 virus that killed untold millions in 1918. Credit: BSIP / Universal Images Group via Getty

The coronavirus is nothing next to the supremely deadly flu virus of 1918, at least not yet. But when you delve into the history of that epidemic, the main comparison with today becomes clear. It's in our "it can't happen here" attitude.

In 1918, modern medicine had made the world seem clean and safe. Scientists had discovered and defeated the bacterial pathogens behind many of history's biggest killers. We hadn't figured out what influenza was, exactly, but it was a known quantity, a seasonal annoyance, really deadly only to the elderly. Doctors weren't required to report it. There hadn't been a global flu outbreak in 25 years, not since the Russian flu of 1891. There was a war on, but the U.S. was congratulating itself on how disease-free its military camps were.

That mindset persisted even after what we now know as the H1N1 flu virus made itself known, likely starting in the U.S. Though its first wave, in the spring, was fast-moving, this flu's effects were relatively mild. Summer stopped it in its tracks.

There was no warning whatsoever that it would come roaring back in the fall, having mutated like an X-men villain into a terrifying killer of the young and healthy. It was a supervirus that seemed nothing like the flu, one that might, within hours of infection, make you collapse in the street, your lungs filling with fluids, gasping for air as your face turned purple and you slowly, literally, drowned.

Fluid on the floor: One of the few 1918 photos to show the victims, here in a makeshift volunteer Red Cross overflow hospital in Oakland. Credit: Underwood Archives / Getty Images

This is the true and still largely unknown story of the flu pandemic of 1918-19, the world's deadliest medical holocaust to date. Unknown? Well, if you're reasonably well up on your history, you probably recall a few facts.

First, that it happened, which is a step up from the 20th century, when it wasn't even taught in college. ("I took a course in virology," says New York Timesscience reporter and microbiology major Gina Kolata in her book Flu, "but the 1918 flu was never mentioned.") Second, that it struck at the end of World War I and was spread in part by troop movements. And third, that it killed between 50 and 100 million people — or more than the combat death toll of World War I and World War II combined — in little over a year.

But you probably don't know the difference between its three waves. Or that the "Spanish flu" name that clings to the pandemic is fake news; it's far more likely to have started in Kansas. Or that it killed more thirtysomethings than sixtysomethings. And while it is true that medical science and practice has advanced significantly since then, it is absolutely terrifying to discover that even though we have nailed down its DNA, we still can't figure out how, where or why that virus mutated.

The defining feature of 1918 flu history is how little we truly know — and how powerless we would be, even now, to stop a successfully mutated virus like that one from killing millions. Here's what we most need to remember right now.

1. We spread lies about how bad it was and where it came from.

U.S. newspapers belatedly begin to report on the flu in November 1918 — with a positive post-racial spin. Credit: Fototeca Gilardi / Getty Images

Remember this next time you hear a talking head on cable news bloviating about how the disease caused by the new coronavirus, or, officially, COVID-19, came from bat soup in China: We've had over a century to try to figure out where and how the 1918 flu started, and we're still arguing about it. But theories that it began in Vietnam or China in 1915 or 1916 lost ground in recent years to a theory that it began in...the very middle of America.

A January 1918 doctor's report to the government from Haskell County, Kansas, stands as the first testament to any unusual flu activity in the world that year. Remember, this reporting wasn't required, so it had to be a big deal. Haskell had many migratory birds and hog farms; we now know that bird and human viruses like to meet and mutate inside the cells of pigs. And Haskell men visited nearby Camp Funston, which reported the first of 24 U.S. Army outbreaks in March 1918. The doughboys then took the virus to Europe.

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One place we can be sure the virus didn'tcome from is Spain. So why did countries around the world immediately start calling it "Spainish Flu" or "The Spanish Lady?" For the simple reason that Spain was neutral in World War I. It had no reason to censor its press, whereas newspapers in the U.S. and Europe were prevented by their governments from printing anything that might lower morale for the war effort.

That, publishers thought, included flu outbreaks. Even when U.S. newspapers started paying attention to the epidemic by listing numbers of new cases, they often put a positive or admonishing spin on their stories. "Worry is useless," advised the Philadelphia Inquirer."Talk of cheerful things instead." One columnist in another paper took to task "nervous and excited people who think every pain is a symptom of the flu."

So irresponsible rumors crept into the gaps left by official reports, as they always do. When the deadly fall wave of mutated flu began in Boston, wild (and false) stories spread that it was a germ warfare attack by Germany. Or that agents of the Kaiser had somehow embedded the sickness in aspirin tablets, made by German company Bayer. Which was, ironically, about the only thing people could take at the time to reduce fever.

And what did Spain get for sounding the alarm and reporting accurately? It got saddled with the supposed origin and the very name of the disease for a century or more. No good deed goes unpunished.

2. World leaders wanted to hide the truth. Then they got sick.

U.S. president Woodrow Wilson arrives in Paris for peace talks, 1919. He may already have flu in this photo. Credit: HULTON archive / Getty Images

In April 1919, U.S. President Woodrow Wilson came down with the flu during its third and final wave — which was deadlier than any outbreak in history except the wave that had preceded it. Wilson survived, but exhibited signs of neurological damage from the sickness and was never the same again. Unknown to anyone at the time, the flu had set Europe on course for World War II.

That's because Wilson got sick in the middle of the Versailles peace conference that officially ended World War I. Now, Wilson may have been an avowed racist, but at least he went to France planning to forge a global peace that didn't involve France trying to bankrupt Germany. Without Wilson as an effective presence, that's exactly what happened. The Versailles treaty was ridiculously punitive and, well, hello, Hitler.

Ironically, Wilson had set the wheels of his own destruction in motion. He had been responsible for many of the previous year's troop movements that spread the flu in the first place. He agreed with his generals that "the shipment of troops must not be stopped for any reason." His surgeon general said "the present generation" had been "spoiled" by excellent medical care, and shouldn't rush to their doctors with "mild cases" of flu.

Wilson was far from the only luminary to have a life-threatening flu encounter. Kaiser Wilhelm II celebrated news of the "Flanders fever," as the Germans called it, because it attacked French troops first. But flu easily crossed trench lines, and the kaiser fell sick before he was forced to abdicate. British Prime Minister David Lloyd George, whose government censored flu reports, got so sick that he had to wear a respirator. This news, too, was censored.

3. Masks were everywhere. They didn't help much.

Unnamed baseball players wearing masks while perfectly healthy, 1918. Credit: George Rinhart / Corbis via Getty Images

It's the one defining feature when you look back through 1918 archives: Everyone, it seems, wore masks. There are pictures of public officials wearing masks, barbers wearing masks, men who didn't wear masks being barred by an officious bus conductor. There are local laws about wearing masks in public, determining the exact thickness of gauze, or cheesecloth, that your mask had to be.

But then as now, the mask craze didn't do much to slow the spread of the virus. Then as now, there was little point in uninfected people wearing them. Then as now, mask use should have been confined to those who were actually sick, and to medical workers.

What might have helped? Obviously, a greater emphasis on hand hygiene. More and faster reporting of flu locations, and a more robust government response. Cutting down on those troop movements as much as possible, and on large gatherings such as the infamous Liberty Bond rally in Philadelphia that infected thousands at once. Within 72 hours, every hospital bed in the city was filled.

But humans will be humans, and they will gather together. How were authorities supposed to stop them from celebrating the end of World War I in the streets that November? What public health campaign could prevent entire villages around the world from coming out to celebrate the joyful return of their soldier boys, dooming themselves in the process? This, perhaps, is why the 1918 flu was rarely taught in schools: It had a grim inevitability to it, one that showcased how powerless we are to prevent catastrophe coming at us from all angles.

It is in these stories that we can glimpse the seeds of inevitable future pandemics. No modern medical system can withstand an influx of flu victims on the scale of 1918. If hospitals get overwhelmed, that's a force multiplier for all kinds of casualties. And unless you ban every conference and concert, or shut down every movie theater, successful viruses will do what successful viruses will do: spread faster than you can stop them.

The best we can do is not be as complacent as the people of 1918 — and choose leadership that offers reality-based responses.

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