About 675,000 people died in the United States during the 1918 Spanish flu pandemic and many of those public health lessons can apply to the current COVID-19 pandemic.
The 1918 H1N1 influenza pandemic, also known as the Spanish flu, was the most severe pandemic in modern history. About 675,000 deaths were reported in the United States.
Although we're only a few months into the COVID-19 pandemic, there are currently many similarities to what we saw then. Not only with the controversy regarding the wearing of masks and the closure of churches, but in the community's response to the pandemic as well.
"We have to be patient," said David Sloane, professor of history at the USC Price School of Public Policy. "It's not that we can't open a little, or slowly, or get back to work, but we have to think about social distancing, masks and gloves.
"We have to be careful about how we do this because this thing is nasty and it's not gone."
The Spanish flu pandemic began in the United States on a military base in Kansas in March 1918. Sloane said it started quietly because it spread slowly, and wasn't very deadly. But as soldiers went off to battle in World War I, the virus exploded.
"Somehow, in the amazing things that viruses do, it does what is known as a genetic shift, and that shift makes it much more virulent, and much more dangerous."
"It begins to spread rapidly in these closed, dense spaces that soldiers are in, and it begins to kill people pretty quickly. And when it comes home, it's a very different virus than when it left."
Around September 1918, the virus came home. Not on jumbo jets like we see today, but on ships full of soldiers returning to Baltimore, Philadelphia, Boston, New York and Los Angeles.
"They dock in San Pedro and try to quarantine them after five or six days, and it's too late. This is an incredibly contagious flu, and so it's into dock workers, into communities, and into Los Angeles. And this is how it happens all across the country."
And just like how health officials closed public spaces like theme parks and beaches in 2020, the same was done in September 1918.
"Concerts, big gatherings, processions and parades. They also closed dance halls, and controversially churches. But not so controversially, they also closed schools."
Many cities ordered that people wear masks. In one photograph, someone is shown wearing a sign that reads "Wear a mask or go to jail."
"They gave out hundreds, if not thousands of tickets for people unwilling to wear a mask. You still had freedom: you could stay home. That's your freedom. You could choose not to go out and infect people. But if you're going to go outside and join the public, then you're part of the responsibility of the public, just like today."
But while large public gatherings were ordered closed, many industries did not shut down entirely.
"They did worry about workplaces, but they didn't take the same type of draconian efforts that we have today."
Photographs show barber shops operating outside, and courtrooms moving to town squares as well. But only thing Sloane said you didn't see happening in 1918: physical distancing.
"Institutionally, they practiced social distancing because they closed churches, schools, saloons and dance halls. But on a personal level, if you look at the photograph, all of the people with masks, they're smushed up together. This is partly because they don't understand the flu."
The 1918 Spanish flu came in three waves: the first in March, which didn't spread that rapidly. The second wave in September, with countless soldiers returning from the battlefield, was the deadliest wave, and the one which resulted in the closures of large gatherings.
But like we're seeing now, the public grew wearisome of the shutdowns in 1918, and began reopening in November. Later that winter, the third and final wave hit the United States.
What lessons have we learned? Sloane said instituting changes in workplaces is something that was effective then - and can be again today.
"There is a possibility that we could learn something from the 1918 flu, that there's this idea of staggered work hours. Maybe not hours, but staggered work stations. Perhaps half the people go back to work on Monday, Wednesday or Friday, and half the people going back on Tuesday, Thursday and Saturday."
"I think we have to be innovative in our social thinking as well as our medical thinking."
While there are certainly differences between the Spanish flu and the current COVID-19 pandemic - such as availability of antibiotics and epidemiological advances - there are things we should keep in mind.
"We've always said those who forget history are doomed to repeat it," said Dr. Cameron Kaiser, Riverside County's public health officer. "And human nature is remarkably consistent unfortunately."
But Kaiser said there's reason to be optimistic.
"There certainly is a lot of controversy as to whether there's going to be a second wave of COVID-19 and what it's going to look like and how it's going to function. But everybody agrees you can't stay locked down forever," he said.
"If we do the right things and do what we know works: we're able to maintain social distancing, facial coverings, and making sure our most vulnerable members of the population are protected, we might be able to reopen safely and we might just get through it."