A science journalist explains how the Spanish flu changed the world

A couple of years ago, journalist Laura Spinney could hardly believe how little people thought about the Spanish flu pandemic, which swept the globe in three deadly waves between 1918 and 1919.

So she wrote a book – Pale Rider: The Spanish Flu of 1918 and How It Changed the World – to bring the tragedy that claimed 50 million lives back into our consciousness,

“It seemed to me there was this huge hole in our collective memory about the worst disaster of the 20th Century. It’s definitely not remembered in the same way as the two world wars – there is some different way we remember pandemics.

“One of the ways I tried to explain it in my book was that, to me, that pandemic is remembered individually as millions of discrete tragedies, not in a history book sense of something that happened collectively to humanity.”

Here she explains what the world was like a century ago and how society changed as a result of the Spanish flu.

What was the Spanish flu?

It was a pandemic of influenza that struck in three waves. The first, mild wave in the Northern hemisphere's spring of 1918 receded in the summer or late spring. A much more lethal second wave erupted in the latter part of August and receded towards the end of that year, and the third wave emerged in the early months of 1919.

We think it infected about 500 million people – so one in three people in the world alive at that time, and it killed 50 million of them. The death toll could have been even higher because there was a big problem with under-reporting at the time. They didn't have a reliable diagnostic test.

Why was it so deadly?

Pandemic flu is much worse than seasonal flu, and we think there have been 15 flu pandemics in the past 500 years. Every seasonal flu started out as a pandemic flu, which was much more virulent because it was new in the human population. Gradually over time, it evolved to become more benign and to live in a more harmonious relationship with humanity.

There are lots of theories for why the Spanish flu was so virulent and they're not mutually exclusive. Some of them have to do with the inherent biology of that virus, and some of them with the state of the world at the time. That pandemic obviously emerged when the world was at war; there were extraordinary circumstances. Lots of people were on the move, not only troops, but also civilians: refugees and displaced persons. And there was a lot of hunger.

All of these factors may have fed into the virulence of the virus. There was definitely something very abnormal about 1918. If you think about the five flu pandemics we've had since the 1890s, none of them has killed more than about 4 million people maximum, whereas we think Spanish flu killed 50 million.

How different was the world in 1918?

There are a lot of similarities, but also a lot of really fundamental differences.

The population was about a quarter the size of what it is today and infectious diseases were still the main killer of people. It was a world that didn't know viruses very well. The first virus had been identified at the end of the 19th Century. So we had germ theory and people understood that microbes caused infectious diseases, but almost every doctor in the world thought they were dealing with a bacterial disease – and that shapes the whole story.

It means they had no reliable diagnostic test and no really good treatments. It was called many different things, which meant we had a problem counting the dead as well.

There were no commercial aeroplanes, so the fastest way you could get around was by ship or by train. Henry Ford had invented his Model T motor car, but they were still the preserve of the rich, as were telephones. And illiteracy was much higher than it is now, which had an impact because the main way that news was transmitted was by newspapers. In illiterate populations news travelled much more slowly and was often distorted.

Why is it called the Spanish flu?

It's a historical accident and unjust because we know for sure that it didn't start in Spain. We don't know where it did start, but there were cases in at least the US, Britain, France and probably some other European countries before it was in Spain.

But Spain was neutral in the war so it didn’t censor its press. And when the first cases broke out there in the spring of 1918, the newspapers reported on them, whereas in these other countries, it was kept out of the news. Those first Spanish cases included Alfonso XIII, the King of Spain, which made it very visible.

So that name kind of stuck, unfortunately, with the encouragement of the other warring nations who were quite happy to point the blame at somebody else. There is a parallel with today because pandemics have always gone hand-in-hand with xenophobia. There's always this human instinct, unfortunately, to point the finger at another country and say it came from there.

How did the Spanish flu change society 100 years ago?

In the short term, there was a jump in life expectancy, because a lot of people who were very ill with, for example, TB, which was a massive killer at that time, were purged from the population. They were probably the first to die of the Spanish flu because they were already in a weakened state. The people who were ill died and the people who were left behind were healthier.

There was also a baby boom in the 1920s, which has always been put down to the war and the men returning from the front. But there is an argument that the flu could have contributed because it left behind a smaller, healthier population that was able to reproduce in higher numbers. Norway, for example, had a baby boom even though it was neutral in the war.

Among those very vulnerable to the Spanish flu were the 20 to 40-year-olds. Normally flu is most dangerous to young children and to the very old, but in 1918, bizarrely, it was this middle age group. There wasn't much of a social welfare net, even in wealthy countries, so lots of dependents were left without any means of support because the breadwinners were taken out by the flu.

One of the great tragedies of 1918 is that those dependents just vanish into the cracks of history. We don't really know what happened to them but we get the occasional glimpse, for example, from a study in Sweden we know that a lot of old people moved into workhouses and a lot of the children became vagrants.

Men were more vulnerable than women overall globally, though there were regional variations. Pregnant women were particularly vulnerable and had miscarriages at frighteningly high numbers because, to fight the virus, the body took resources away from the womb and the growing foetus. Some of those babies survived and we know now there's a lifelong effect called foetal programming. That generation was physically and cognitively slightly reduced. They were more likely to suffer from heart attacks and to go to prison – and came of age just in time to go and fight in the Second World War.

How did healthcare change after the Spanish flu?

In many Western countries, there was a turning away from science after the pandemic because people were disillusioned with it. From the 1920s, for example, in America, alternative medicine took off in a big way and spread around the world.

But at the same time, in countries that had not really embraced the scientific method, you see the opposite effect. So China becomes a little bit more scientific after the pandemic. There's a move to better disease surveillance, better public health, more organized collection of healthcare data, because they saw that to prevent future pandemics they needed to turn towards science.

It gave a big boost to the concept of socialized medicine and healthcare, which no country had really got around to organizing yet. The pandemic is what gave the stimulus to do that because there was a realization that a pandemic was a global health crisis you had to treat at the population level. You couldn't treat individuals and there was no point in blaming individuals for catching an illness or treating them in isolation.

Russia was the first, followed by Western European nations, to put in place socialized healthcare systems. Along with that comes epidemiology, the search for patterns and causes and effects of patterns in healthcare. The baseline health of populations started to become much more transparent, and much more visible.

What parallels are there with today’s coronavirus?

The Spanish flu was democratic on one level. It could infect anyone: British Prime Minister David Lloyd George came down with the flu and Boris Johnson has had COVID-19 today. Nobody is, in theory, spared.

If you look at the population level though, there's a very clear disparity and basically the poorest, the most vulnerable, the ones with the least good access to healthcare, the ones who work the longest hours, who live in the most crowded accommodation, and so on, are more at risk.

But in 1918, it was a time of eugenics-type thinking and it was perceived that those people who were more prone to the flu were constitutionally somehow inferior, that it was somehow their fault. Of course eugenics was completely discredited after the Second World War.

Today, we understand that the reason those poorer groups in society are more vulnerable is because of the environment they inhabit and the fact that they don't have access to better healthcare. That effect is strong in every pandemic and, unfortunately, it's likely that developing countries are the ones that are going to bear the burden of this pandemic.

What protective measures were put in place in 1918?

We've always understood that in order to contain contagion you have to separate sick and healthy people. Concepts like isolation and quarantine are very old and they predate germ theory. So we didn't have to understand that diseases are spread by microbes to understand how to rein them in.

Public health measures were put in place in some parts of the world. America did very well, Europe didn't do too badly, but there was a war on and it wasn't possible to keep those things in place very effectively, or for long enough.

The dates of the waves were dependent on where you were in the world. They came later in the Southern hemisphere, which meant Australia had the luxury of seeing this thing approach in space and time from the north, and took advantage of that to put in place maritime quarantine.

It managed to keep out the lethal second wave in October 1918, which is one of the rare exceptions of public health measures really working that year. But they lifted it too soon and the third wave of infection of early 1919 came into the country and killed 12,000 Australians. But it would have been much, much worse if they had not put the quarantine in place when they did.

Will COVID-19 be remembered in history?

It's too early to know if we’ll remember this one, but the precedents suggest we won’t. There were two other flu pandemics in the 20th Century: the 1957 Asian flu and the 1968 Hong Kong flu. They killed about 2 million and 4 million people, respectively. We are nowhere near those numbers yet and yet we don't compare this pandemic to them. We immediately head for the enormous one in 1918, which is strange in itself. But they were much worse than this one to date, and we don't remember them.