Alice Wolowitz, a student nurse, began her shift at a hospital one morning in Philadelphia. She fell sick during the shift, rapidly declined and was dead that night.

That was 1918, and people were collapsing and dying everywhere from a Spanish flu pandemic. Philadelphia’s 31 hospitals were full and turning away patients, who offered huge bribes to get in. Police officers with surgical masks were sent to pick up bodies from homes, but 33 police officers died within weeks.

“In virtually every home, someone was ill,” John M. Barry writes in his book about that pandemic, “The Great Influenza.” “People were already avoiding each other, turning their heads away if they had to talk, isolating themselves. The telephone company increased the isolation: With 1,800 telephone company operators out, the phone company allowed only emergency calls.”

Sports events were canceled. Theaters closed. Shaking hands was made illegal in Prescott, Ariz. Philadelphia hurriedly set up six more morgues. Families put crepe paper on doorways to signal a death inside — and crepe was everywhere.

That Spanish flu epidemic of 1918, which killed at least 50 million people worldwide, has been the benchmark for pandemics ever since. For decades public health experts have called for preparations for another “big one” — yet adequate preparations were never made.

Nobody knows if the coronavirus will be a “big one,” for it may still fizzle. As of this writing, only one person is known to have died from it in the United States, while thousands routinely die annually from the seasonal flu. But increasingly, experts are saying that we should get ready just in case.

“Are we seeing a replay of 1918?” asked The New England Journal of Medicine, a publication not associated with alarmism. Bill Gates, who for years has been warning presciently about the danger of pandemics, bluntly cautions that this virus could be a “once-in-a-century pandemic.”

“I hope it’s not that bad, but we should assume that it will be until we know otherwise,” Gates said, and that seems prudent.

While figures are uncertain, the coronavirus may kill 2 percent of those infected; if correct, that would be similar to the lethality of the 1918 flu (it’s also possible that many more people are infected without significant symptoms, which would make the death rate quite a bit lower). Another similarity with 1918 is that the United States and the world are unready for a pandemic.

“We’re amazingly unprepared,” Dr. Irwin Redlener, a Columbia University professor and director of the National Center for Disaster Preparedness, told me.

President Trump exaggerates threats from caravans of migrants or from a hobbled Iran, and he has diverted billions of dollars from the military to build a border wall that smugglers hack apart with $100 saws. But he has not been attuned to pandemic threats: In 2018 the White House removed the position on the National Security Council to fight pandemics, while seeking to scale back anti-pandemic work to about 10 countries from 49. Experts warned at the time that this was dangerously shortsighted.

At a time when we need wise, scientifically informed leadership, we find ourselves with a president with little credibility and an antagonistic relationship with scientists. It doesn’t help that during the Ebola crisis of 2014, Trump was one of the most fiery critics of evidence-driven policies that actually succeeded in ending the outbreak.

The United States is also vulnerable because of longstanding deficiencies in our health care system. We are the only major rich country without universal health insurance and paid sick leave, and we have fewer doctors per capita than peer countries.

Consider a Florida man, Osmel Martinez Azcue, who returned from China and found himself becoming sick. As The Miami Herald reported, he might normally have gone to a drugstore and bought over-the-counter flu medicine. But because of the risk of coronavirus he did the responsible thing and sought medical attention: He went to a hospital for testing. In the end, it turned out not to be coronavirus — but he was billed $3,270.

We must ensure that no one is deterred from seeking help by the costs. The White House and Congress should immediately establish a system to ensure that patients need not pay for coronavirus testing and treatment. We should also ensure paid sick leave. Do we really want to go to a restaurant where a coughing, sneezing food preparer still goes to work out of financial need?

William A. Haseltine, president of a think tank called Access Health International, told me that a vaccine might take at least six to eight months to develop and test — some other estimates are longer — and this should involve an immediate federal investment through Project BioShield. We also need better diagnostics and treatment as well as more ventilators to keep people alive.

Dr. Peter Jay Hotez, an expert on global health at Baylor University, emphasized to me the need to support front-line health workers and keep them from becoming infected.

“If we see a situation in the U.S. like we saw in Wuhan — more than 1,000 cases among hospital workers and five or six deaths — it’s game over,” he said. “Health workers lose confidence, and things start to fall apart.”

Hotez said that one crucial step is simply ensuring that all health workers have enough personal protective equipment.

We may also have to think about reducing occasions when people are crowded together; that may mean more people working from home to avoid offices, buses and subways. It may mean avoiding sports events, school assemblies, parties and even unnecessary visits to crowded doctor’s offices — this is a time to develop telemedicine.

I have two family graduations this spring, and who knows if they will take place? Experts can’t answer the questions that we all have, but they say that we will get through better if we make preparations while relying on science and evidence rather than on muddled political leaders trying to talk up markets or score political points.