The flu pandemic that ravaged Chicago: Could it happen again?

One hundred years ago, one of the worst plagues in history — a pandemic of Spanish influenza — spread across the globe and slammed into Chicago. The 1918 flu pandemic killed quickly — sometimes in less than a day — and indiscriminately. It attacked not only the elderly and weak, but otherwise healthy adults in their 20s and 30s.

The flu quickly overwhelmed public health officials. On a single October day, Chicago authorities reported 135 deaths and 1,342 new cases. By the following week, there were more than 2,000 new cases a day. All told, about 10,000 Chicagoans were among the 675,000 Americans who died of the flu. Across the globe, an estimated 50 million or more died, often from a secondary infection, bacterial pneumonia.

The answer to the question in our headline: Could a pandemic sweep the globe again? Yes. There have been three pandemics since the 1918 scourge, the last in 2009.

The major differences between now and 1918: Flu vaccines and better medical care, including antibiotics and other treatments, now spare many lives that would have been lost a century ago. Even a regular flu season, however, is lethal. Last season’s flu outbreak killed 80,000 Americans, including 180 children. There were spot shortages of antiviral medications like Tamiflu.

That’s why getting vaccinated is still the smartest way to protect yourself, your community and your world. Vaccines may be more or less effective every season, depending on whether manufacturers correctly predict which strains will circulate. If they figure wrong, more people are vulnerable. But that’s not an argument to shun the vaccine.

“I’m tired of hearing people say, ‘Well, I didn’t get sick and I didn’t get the flu shot.’ Or, ‘I don’t like it, my arm hurts,’ ” Surgeon General Jerome Adams said recently. “Those 80,000 people who died last year from the flu, guess what? They got the flu from someone. So it’s critically important that we impress upon folks that it is not just for them. It’s their social responsibility to get vaccinated.”

Preparing for the next pandemic should be a top national security issue, argue authors Lisa Monaco and Vin Gupta in Foreign Policy. Monaco, a former homeland security adviser to President Barack Obama, and Gupta, a physician and assistant professor at the University of Washington, report that investments “to contend with such outbreaks have declined to their lowest levels since the height of the Ebola response in 2014, with U.S. federal dollars cut by over 50 percent from those peak levels.” That’s shortsighted.

The ultimate goal is a universal vaccine that would offer almost-complete protection against the disease for years, if not for life, with a single shot. That’s a tall order given that medical researchers are confronting a shape-shifting, fast-mutating virus dedicated to devising ways to evade the body’s defenses. But it isn’t impossible. “Vaccines are the best tool” to battle flu viruses, Michael Osterholm, a University Of Minnesota infectious disease expert, tells us. Those investments in better vaccines will reap huge dividends, he says, in lives saved.

While that work continues, the best defense is to be vaccinated, to wash hands and to keep them away from your face. No one knows how severe this season will be. But this year, as every year, preparedness is the best antidote to fear.

And the next time you’re strolling through a cemetery that was accepting burials in early decades of the 20th century, note how many lifespans ended in 1918.