My grandmother died in the mid-1970s at the age of 94. She had lost a son in the Spanish influenza outbreak of 1918. Slumber visits the very old at any time of the day so that dreams and reality begin to merge, like cream and the tea that it’s been poured into. However, some facts she clung to until the day she died and she grieved for 16-month-old “Baby Jimmy” until the end.

“You never forget,” she used to say in her Irish brogue.

Last December, when Tommy Thompson, secretary of the U.S. Department of Health and Human Services announced that he was stepping down, he warned about the “huge lethality” of avian flu H5N1, which could kill 70 million people worldwide.

“And we do not have a vaccine,” Thompson said. “We do not have a therapy for H5N1.” He added, just to make sure we got the point, that the danger of an outbreak of H5N1 “is a really huge bomb out there that could adversely impact on the health of the world.”

War plays a big part in history. So does disease. Seems like ever once in a while Mother Nature gets bent out of shape enough to decimate us.

We can only hope that she’s not getting ready to do so again, though Thompson’s warnings certainly give pause. This is not, after all, a conspiracy theory caught on the Web. This is a high-ranking government official and you’ve got to think that he would not publicly mull the possibility of 70 million fatalities without first giving it an awful lot of thought.

Robert S. Zimmerman is HHS’s top guy in region III, which is Delaware, Maryland, Pennsylvania, Virginia, West Virginia, and the District of Columbia. He’s stationed in the Public Ledger Building at 6th and Chestnut Streets.

I asked him what the government has planned in case of an outbreak and he kicked me to a PR guy in Washington who told me that HHS doesn’t “engage in speculative discussions.”

OK. But meanwhile, we regular folk can only hope that the experts are coming up with a plan that will work a lot better than the one used by the people in charge of Philadelphia in 1918. “Muddling through” would be too kind a description to tag on that response. The city’s reaction to the catastrophe is rife with mismanagement, miscalculation, and misfortune. Flu-friendly decisions at every turn guaranteed that corpses would pile up.

The 1918 flu didn’t need much encouragement. When it had finally run its course, the outbreak had killed 21 million people worldwide, more than twice the number killed in World War I, which had been winding down at that point.

When the disease hit Philadelphia in September 1918, the city assured the public that the flu would not spread beyond military facilities. Despite evidence that the flu was indeed reaching into the general population, a Liberty Loan Drive rally was allowed to go off as planned on Sept. 28, 1918. Huge crowd. Highly contagious and deadly disease. Not good. Eventually, about 13,000 people in Philadelphia would die before the epidemic ran its horrible course.

In the Aug. 23 issue of the New Yorker, author Adam Gopnik — reviewing recent books about World War I — discussed the struggles with which we amateur and professional gazers into crystals confront.

“All these historians find themselves contending with the issues of historical judgment: how much can you blame the people of the past for getting something wrong when they could not have known it was going to go so wrong? The question is what they knew, when they knew it, if there was any way for them to know more, given what anyone knew at the time, and how in God’s name we could ever know enough about our own time not to do the same thing all over again.”

In the case of the flu epidemic of 1918, the historical consensus is that those in charge in Philadelphia got it tragically wrong, when they could have just as easily have gotten it right. People still would have died. But how many?

Gopnik asked “…are there lessons in history, or just stories, mostly sad?”

That’s a question that I never asked my grandmother. It’s one that I hope I never have to answer.