Un-remembered but Unforgettable: The Spanish Flu Pandemic

Daniel Flecknoe. The First World War and Health. Leiden, March 2020.

Introduction

In 1918, during the final months of the First World War, an influenza epidemic swept across the world. This strain of influenza was unusual, in that it was particularly deadly among 20-40 year olds, the age group typically least at risk from flu-related mortality. Many victims of the pandemic appear to have died from respiratory failure due to secondary bacterial infections, which medicine at the time lacked the antibiotics to treat. Wartime censorship and military objectives often obstructed the public health response, and troop movements helped to spread the disease.

Worldwide, during the years 1918-19, the ‘Spanish Flu’ pandemic is estimated to have killed between 50 and 100 million people. Despite its massive impact on the world, the pandemic was largely written out of early 20th century history, possibly because of a wish to focus on the more heroic narrative of the war. The long-term repercussions of the ‘Spanish Flu’ lasted for generations, and have had both positive and negative impacts on societal resilience. This chapter discusses the pandemic, its impacts and effects, as well as its implications for modern public health practice.

The word ‘influenza’ was first coined during an outbreak in Renaissance-era Italy, in which it was noted that the populace attributed the disease to the malevolent ‘influence’ of the stars. Today, influenza still retains some of the mercurial and enigmatic character lent to it by this early classification. In abbreviated lay parlance it is often used to describe a mild cold (“a touch of the ‘flu’”), or the perceived malingering and tendency to exaggerate trivial symptoms by men (“don’t mind him, he’s just got man-flu”). And yet, in its pandemic form it remains at the top of public health risk registers for most developed nations. These contradictions are embodied in the largest ever recorded influenza epidemic, which, despite being one of the single deadliest events in human history was, and is still, mostly overshadowed by the First World War (which killed many fewer people). Not unlike a solar eclipse, when a vast object (the Sun) is obscured by a smaller one (the Moon), the explanation for this phenomenon can be found in their relative proximity to our point of view. In the case of the ‘Spanish Flu’ pandemic, which this chapter will discuss, it appears that the First World War, with all of its heroic, tragic, and stirring tales of world-changing but most importantly human agency, has always been much closer to the kind of narrative that we want to tell about ourselves, and of 20th century history. But history is not only composed of the stories that people want to tell, and there is often as much or more to learn from the times when uncaring nature collaborated with unforeseen consequences in order to humble the best efforts of medicine and society. This is one of those stories.

A Brief History of Infectious Disease Control

Human progress towards understanding and controlling infectious diseases throughout history has been slow and uneven, with occasional flashes of impressively forward thinking. In the 5th century b.c., for example, the philosopher Empedocles is reported to have successfully rid the city of Selinus of malaria by diverting rivers in order to remove a stagnant swampland. Trial and error over the next two millennia largely established the value of isolating the sick and enacting quarantines to prevent epidemics from entering uninfected cities or towns (or confining them in infected ones). The famous self-imposed quarantine of the Derbyshire village of Eyam during the Great Plague of 1665 reinforces the point that knowledge of the causal organism is not always necessary in order to enact successful counter-measures to its spread. Nevertheless, from the Enlightenment onwards, such knowledge was being sought with increasing energy and technical sophistication.

This trend of historically slow progress towards understanding the true causes of disease went into abrupt overdrive in the generation prior to the First World War. Pasteur’s discovery of bacteria in the 1860s gave rise to Germ Theory, which led to radically beneficial changes in medical practice relating to infectious disease control. Vaccines began to be developed, which along with improvements in clean water and sanitation, meant that many of the major scourges of the 19th century were dramatically reduced by the onset of war in 1914. Disease-causing protozoa and fungi had also been identified, treatments were becoming more effective, and well-reasoned guesses were beginning to be made about the existence of tiny ‘filter-passing’ organisms that were too small to see under a microscope or to be impeded by a standard bacterial filter, yet nevertheless still had the power to make people ill. These hypothesized organisms, speculatively called ‘viruses’ (meaning ‘poisons’ in Latin), were known to be rendered harmless by extremes of temperature, and so were thought to be alive in some sense, but for now their existence was only a matter of conjecture.

Despite the growing ascendency of Germ Theory in the early 1900s, many senior doctors at the time of the First World War had done their medical training prior to its discovery, so some older ideas (such as the ‘miasma’ theory of disease) still persisted. The disciplines of bacteriology and public health were still both still in their infancy, but becoming better recognized (especially in the military) as being important for epidemic control. Pathology and laboratory sciences, which could be highly dangerous pursuits in the absence of modern biohazard precautions, were used to good effect in the Spanish-American war of 1898 and also during the Balkan Wars of 1912-13. This represented the beginning of a much needed counter-offensive in the battle between armies and communicable diseases, in which the microbes had previously held a decisive advantage. The number of recorded deaths from infectious disease in the Peninsula, Crimean, and South African Wars, and the American Civil War (all of which occurred in the century prior to the First World War) each exceeded the recorded deaths from combat in those conflicts by a wide margin. The First World War would bring about some major victories for the human side of this inter-species conflict, and also some significant defeats, the most devastating of which is the subject of this chapter.

Influenza was a disease that both gratified and frustrated practitioners of the science of medicine during this period. In its habit of mostly killing the elderly or infirm it was sometimes regarded as a merciful disease, and also a relatively congenial one for doctors who were paid per visit and could expect a bonus if their patient recovered. An illness of which many suffered but relatively few died, was therefore good for business. However, its causal organism still eluded scientific enquiry. A bacterium, now known as Haemophilus influenzae, had been identified as being so commonly found in the lungs of autopsied influenza victims that some scientists thought it was the illness’ cause, while others suggested that one of the hypothesized ‘viruses’ was a more likely candidate. There had been an influenza pandemic in the late 1880s, which killed roughly 1 million people around the world, and which was observed at the time to disproportionately affect soldiers in crowded barracks. At the outbreak of the war in 1914, medical personnel on all sides of the conflict were mobilized in large numbers to fight the familiar military diseases of typhus, measles, and cholera. No one was prepared for what they actually faced.

The Pandemic

The precise beginning and end of the ‘Spanish Flu’ pandemic—so called because neutral Spain actually reported on the disease, while belligerent nations officially suppressed the news—is difficult to cleanly define. The generally agreed epidemiological pattern is of three sequential waves of varying severity: in the spring of 1918 (low fatality), autumn of 1918 (high fatality) and spring-summer of 1919 (moderate fatality). However, some researchers have drawn attention to earlier outbreaks of atypical respiratory disease in British army barracks and French military camps in 1916-17. Under-reporting in the chaos of the First World War was a significant problem, and influenza was easily mistaken for some of the other febrile and debilitating illnesses caused by the unhygienic conditions that soldiers lived in, such as Trench Fever (now known to be caused by Bartonella Quintana infection transmitted by lice). Indeed, it is not completely certain that all three waves were caused by the same disease. Genetic testing has thus far only been possible on samples taken from victims of the second wave, and some people at the time thought that this must be a wholly new disease due to its unprecedented virulence. However, the working assumption among most scientists and historians is that the H1N1 influenza virus, identified in the lungs of permafrost-frozen corpses in the Arctic, was responsible for all three peaks of the pandemic. We will proceed upon that assumption.

The disease, which at the time was known variously as ‘Spanish Lady’, ‘French Flu’ (in Spain), and the ‘Purple Death’ may have had both avian and swine elements to its genetic make-up. Its origins have been variously suggested to have been Europe, Southern China, or the Midwest of America. Wherever it originally came from, it detonated in early 1918 at the epidemiological Ground Zero of the Western Front—an area that had already been the setting for some of the most profound, noble, and yet ultimately futile human suffering in recorded history—and promptly made conditions there a good deal worse. What were described at the time as the “relentless needs of warfare”, swept virtually all public health considerations aside and created the perfect storm of overcrowding and forced troop movements across and between continents to spread the disease far and wide. This novel strain of H1N1 successfully exploited a man-made ecological niche created by the greatest mass population movements in history; to take the most unambiguous example, during the last six months of the war, an estimated 1.5 million American soldiers crossed the Atlantic to join the fighting in Europe. They brought fresh reserves of manpower, weaponry, and stamina to bolster the exhausted Allied armies. But with influenza then raging through US military training camps, they also brought another, much less welcome, cargo. Although the age distribution of influenza cases in 1918 was similar to the usual picture, the distribution of deaths was highly atypical. As previously mentioned, influenza was primarily known for carrying off almost exclusively the very young and the very old.

Men aged 20-40 years old were disproportionately likely to die during the pandemic. Although the most intuitive explanation for this trend would be that the privations of trench warfare made military age men more susceptible to complications, the pattern also held true for civilians and for those living in non-belligerent countries. The diary of a soldier who lived through a troop ship outbreak observed that “[t]he strange thing about this sickness is that the big strong men seem to get it the worst and are the ones that die”. Mortality was largely attributable to secondary bacterial pneumonia, which created the cyanotic ‘heliotrope’ discoloration on the faces of the dying, from which the ominous nickname ‘Purple Death’ was derived.

Years later, medical personnel who saw the disease first-hand still marvelled at the “furious speed” with which it spread, not only through communities (military and civilian) but across continents. Historical conspiracy theorists would find great scope in the contemporary and modern reports that the pandemic seemed to appear in many parts of the world simultaneously, so rapidly did it travel. Patriotic fervour and demonization of the enemy gave traction to Allied rumours that the Germans were engaging in biological warfare, possibly through gases released from U-boats. Some also observed that the symptoms of ‘Spanish Flu’ closely resembled those of phosgene gas poisoning. With the benefit of access to the historical records of both sides in the conflict, and a clear understanding of scientific progress at the time, we can safely dismiss these speculations while still being awed by the speed with which a pandemic could spread around the world even at the very beginning of the era of globalisation.

‘Spanish Flu’ appears (no doubt there is some reporting bias here) to have engulfed almost the entire world in a matter of weeks. From the Allied side of the Western Front it leapt across No Mans’ Land to the German side, likely by way of captured enemy prisoners, and thereafter was quickly spread to other theatres of war. Away from the battlefield it typically appeared first in port cities, where soldiers, sailors, and cargo ships were arriving from other parts of the world, and then radiated out via rail networks. Isolated island nations were sometimes hit hardest by the second, more deadly wave, especially if they had missed out on the immunity conferred by the milder first wave. Western Samoa, where 25 per cent of the population died from the pandemic in the autumn of 1918, is a good example of this phenomenon. Some cultures were also particularly vulnerable because of social customs that enhanced house-to-house disease transmission, such as the practice of visiting bereaved neighbours in order to pay respect to the dead.

Public health response to the pandemic was patchy, due in part to incomplete knowledge and in part to the greater priority assigned by most decision makers to military objectives. In some areas, such as Australia, successful quarantine measures were enacted once news of the second wave began to arrive, and this may well account for their proportionally low (although still significant) mortality figures. In other parts of the world, especially those most befuddled by the fog of war, folk remedies and quack cures abounded in the absence of a well-organized state response. The civilian populations of belligerent nations were left especially unprotected against disease outbreaks, not only by the nutritional austerity of wartime, but also because a large percentage of their trained medical and nursing staff were overseas, seconded to the military. And the military, for their part, were too often living in overcrowded, poorly-ventilated quarters, which dramatically enhanced the spread of disease within the ranks of those fighting the optimistically named ‘war to end all wars’.

Isolation of the infected, one of the tried-and-tested methods of infectious disease control, was frequently made impossible by the unwillingness of military leaders to prioritize public health over war-winning objectives (ill. 11.3). Patriotic parades and other ceremonial military-civilian gatherings went ahead in cities across America during the second wave, despite medical advice that this would only facilitate the spread of this newly-lethal disease. The troop ships continued to set sail. Since many doctors still believed that influenza had a bacterial cause, vaccines against what were thought to be the likely candidate micro-organisms were widely used, to little or no avail. Misinformation was sown, as the failure to locate Pfeiffer’s bacillus in the lungs of some of the deceased was proclaimed as conclusive evidence that the disease was not influenza. Gauze facemasks were used in many parts of the world, which may have offered some slight protection, as although they were not fine enough to stop viruses they could block the larger dust motes and particulates upon which viruses could be riding. In San Francisco, where the failure to wear a mask in public was made illegal, there was considerable libertarian resistance against what was perceived to be an unconstitutional interference with personal liberty.

The war, and (by modern standards) very poor data collection systems, frustrated contemporary efforts to both measure the true scale of the catastrophe and to effectively combat it at the time. The estimated number of deaths worldwide, from all three known waves of the pandemic, has been gradually revised upwards over the last 100 years as better information has become available. The consensus view over the last decade has been that the ‘Spanish Flu’ killed between 50-100 million people.

How did the Pandemic Affect the War?

The First World War has often been cited as a turning point in the history of warfare. In wars prior to 1914 it was almost invariably the case that deaths from infectious diseases would exceed the deaths caused by combat. The scales were being tipped from both directions by the start of the 20th century, with increasing medical knowledge successfully reducing outbreaks of disease, as well as curing those who contracted them, and also by the increasing efficiency of battlefield weaponry, killing the enemy in far greater numbers than ever was possible before. However, whether you consider the First World War to be in fact the tipping point, or merely the last triumph of disease’s long ascendancy in wartime deaths, very much depends upon how you factor in the ‘Spanish Flu’. If civilian casualties of the pandemic are included in the calculation then diseases could have killed up to ten times as many as were killed by combat between 1914 and 1918.

In terms of the effect of the pandemic on the course of the war, there is necessarily some uncertainty about this. The opinions of observers at the time, and those of historians up to the present, can provide us with probabilities and informed opinion, but since it is not possible to know what would have happened if the ‘Spanish Flu’ had not emerged when it did, there will always be an element of speculation. Other infectious diseases that were prevalent in sections of the military during the First World War are generally thought to have had the effect of prolonging it. Some of these diseases were due to the abysmal conditions that men were fighting in (such as Trench Fever), and others due to unfamiliar pathogens endemic to the theatres of war that soldiers were travelling to fight in (e.g. malaria). They took a severe toll on the fighting strength of the belligerent nations, and as such are considered likely to have delayed any possible military victory by either side.

‘Spanish Flu’ certainly sapped the strength of all sides in a similar way. By July of 1918 there were widespread outbreaks on both sides of the conflict, causing significant morbidity and mortality among the soldiers who would otherwise have been mustering for last ditch strikes against the enemy. Those victims that ‘Spanish Flu’ did not kill, it temporarily incapacitated, and the ill were (in some ways) more of a burden to the military than the dead, in that they needed caring for, thereby diverting resources from the fighting. Also, at a time when both sides were relying more and more heavily on reserve troops to relieve the exhausted frontline divisions, the pandemic frequently picked them off as they arrived; new recruits, lacking any partial immunity from exposure to previous waves of the disease along the Western Front, had by far the highest mortality. The U.S. military, entering the war in 1917 on the Allied side, were heavily affected, by some estimates losing at least as many soldiers to ‘Spanish Flu’ as they did in combat. All of this would argue for the pandemic having probably lengthened the war.

However, the alternative possibility is also worth considering. The ‘Spanish Flu’ struck in the final year of the war, at a moment when Germany was close to defeat but still had some important cards left to play. In the spring of 1918, German forces on the Western Front launched the Kaiserschlacht (Kaiser’s Battle), intended to be a series of decisive blows that would drive the Allied forces back across France until their backs were against the English Channel. They were strengthened by large numbers of troops and resources from the Eastern Front, redeployed following the withdrawal of Russia from the war. American troops were streaming across the Atlantic to bolster Allied forces, but for the moment, the Germans held the numerical advantage. The early offensives of the Kaiserschlacht were successful, and the Allies were forced to retreat. However, a combination of factors prevented the German forces from consolidating their early gains, and the momentum faltered, bringing to an end their final realistic hope for victory. One of those factors was the first wave of the ‘Spanish Flu’.

Other factors included exhaustion, low morale, and political upheavals within the German army. The German High Command had been successful in fomenting a rebellion in Russia that removed their eastern enemy from the war, but the same anti-war sentiments which had animated the revolutionary workers’ councils (or ‘Soviets’) were also spreading through their own ranks. However, General Erich von Ludendorff, commander of the German forces, wrote after the war that the pandemic had been a significant factor preventing the success of the Kaiserschlacht. Without that victory, Germany was no longer in a position to win the war, and was consequently forced to begin considering the terms of surrender. It could be argued that von Ludendorff would have had a bias in favour of attributing the Kaiserschlacht’s failure to the pandemic, since he could hardly be blamed for it. However, it is also plausible that without the impact of the ‘Spanish Flu’ on what could have been a decisive turning of the tide against the Allies, the war could have gone on much longer.

Although the historical connection is now well established, popular narratives of war do not tend to prominently feature the role that infectious diseases can play in bringing about either victory or defeat. During the American War of Independence, George Washington had his soldiers vaccinated against smallpox, which was then endemic in North America. As a result, the Continental Army lost many fewer men to the disease than the British and Loyalist forces, which is now considered by historians to have been a significant factor in ensuring victory for what later became the United States. As with the impact of ‘Spanish Flu’ on the outcome of the First World War, this interpretation rarely prevails over the more nationalistically affirming ‘superior tactics, valour and force of arms’ explanation for military outcomes. As the anthropologist Jared Diamond has observed, “The winners of past wars were not always the armies with the best generals and weapons, but were merely those bearing the nastiest germs to transmit to their enemies”.

It scarcely needs to be said that the ‘Spanish Flu’ had enormous impacts beyond any effect that it may have exerted upon the outcome of the First World War. Around the world, 500 million people are thought to have been infected over the course of the pandemic, which continued well into 1919. In the postwar years, while millions of civilians were dying of typhus, tuberculosis, and other diseases associated with the malnutrition, overcrowding and poor sanitation in refugee camps, bombed cities, or devastated farming communities, ‘Spanish Flu’ was also quietly taking its toll. The global social and economic impacts were exacerbated because the dead were so often those of productive working age, causing labour shortages in cities and famines in rural areas. It took as many as 100 million lives and immiserated many times that number, and then, seemingly, it vanished from the public memory. Histories of the period published in the first half of the 20th century rarely mentioned it, and popular culture gave it little or no attention. But forgotten or not, it continued to have an impact on society, medicine, and resilience.

Longer Term Impacts

The most truly awful, yet plausible, long-term impact of the ‘Spanish Flu’ pandemic is that it may have contributed to setting the scene for the Second World War. In April 1919, evidence suggests that US President Woodrow Wilson became a victim of the third wave of the pandemic. He collapsed during peace talks at the conference of Versailles, suffering from a high fever, cough, and confusion, all symptoms consistent with influenza. Wilson had expressed a desire for a peace agreement that did not excessively punish the German people for their country’s actions during the war, and in earlier negotiations he had strongly argued, against his European counterparts, for a leniency that they were not otherwise inclined to bestow. His temporary removal from the negotiations, and the weakness and inattention to detail that he reportedly showed when he recovered enough to return, may well have caused the sanctions eventually levied against the defeated German nation to be harsher than they might otherwise have been. Given the extent to which the provisions contained within the Treaty of Versailles contributed to the rise of extremist politics in interwar Germany, that one single case of ‘Spanish Flu’ could indeed have been an indirect cause of the Second World War.

Although the pandemic does not appear to have lingered in the collective consciousness, just like the war the resultant social changes would not be quick to fade away. Millions of volunteers had mobilized to care for the sick, putting their own lives at risk to deal with a national and international emergency. In Britain, the phlegmatic ‘keep calm and carry on’ spirit, later made famous by Second World War propaganda posters, was invoked as a duty by senior doctors with regards to the ‘flu’. However, it would be frivolous to suggest that any benefits in terms of community cohesion or stoicism could possibly outweigh the societal burden created by the loss of so many people in the middle generation, at a time when so many others had already been taken by the war. The pandemic cast a long shadow over the communities it touched for generations to come, even if its name was lost to memory.

The question of exactly how and why the ‘Spanish Flu’ came to be so neglected in the histories, narratives, and memories of the 20th century is an interesting one. From a medical point of view, there is no doubt that the sense of collective failure which was attached to the experience could have influenced many doctors to want to wash it from their minds. The triumphalism of the previous generation’s rapid progress in gaining ascendancy over hitherto ungovernable infectious diseases came down to earth with an ego-jolting thump when confronted by a worldwide plague, which the science of the time was powerless to either understand or treat. It was an aberration in the anthropocentrically-anticipated course of events—that of human science steadily and irrevocably mastering nature—and which was therefore complacently categorized as an ‘isolated’ throwback that could be safely stricken from the record. It had no comfortable place within the heroic narrative of the First World War, in which the densely-populated cemeteries of the Western Front were named after the battlefields, rather than the causes of death of those that populated them. Extraordinarily, even in the immediate aftermath of the war, historians were recording that armies practically decimated by the pandemic suffered from “no major epidemic problems”.

While the pandemic represented a defeat for medicine, both in terms of its public and self-image, it could be considered a relative success for the profession of nursing. The medical treatments and prophylaxis available were largely ineffective, and in fact some of them may have actively made the situation worse. The use of high doses of salicylates (aspirin) to control fevers has been suggested as a possible contributor to high mortality during the pandemic, as they are now known to have a detrimental effect on lung function when administered in large quantities. The only truly effective treatment was the old nursing standard of ‘tlc’ (tender loving care), which was administered in large measure by the millions of mostly-female volunteers who rallied to care for the sick across the world. Public recognition of the value and importance of nursing care, especially by those millions for whom it had been life-saving in the absence of effective medical interventions, was undoubtedly enhanced by the ‘Spanish Flu’ experience. Although the pandemic was not explicitly mentioned in the relevant parliamentary discussions, it seems unlikely to be a coincidence that the first British legislation to create a professional framework for nurses was passed in November 1919.

Communication and Conscience

Another long term effect of the pandemic was to shine a light on the subject of wartime propaganda: its uses and abuses. Even before the pandemic, the First World War was spawning hysterical ‘end times’ movements who saw signs of Armageddon in the unprecedented scale of the conflict. The advent of a mysterious plague sweeping across the world lent even greater fervour to these theological convulsions. These reactions emphasize the need for clear and open public communication during such crises in order to gain the public trust, to inform and reassure them as appropriate. At a time when the public communication tools of many governments were fully mobilized to the goal of providing deliberate misinformation in the service of the war effort—demonising the enemy and exaggerating military victories—this was always going to be a significant challenge. European newspapers were often forced by authorities to either not report on the ‘Spanish Flu’, or to say that the disease was far milder than was in fact the case, because of the effect it was feared the truth would have upon public morale. Wartime propaganda unquestionably hampered public health efforts, as rudimentary as they were in the early 20th century, to control the pandemic. In the era of ‘fake news’, very similar barriers of deliberate misinformation are likely to be encountered by those attempting to transparently inform or educate the public about how to protect themselves from any future pandemic.

Another still-relevant issue which the ‘Spanish Flu’ threw into sharp focus is the balance between protecting the health of the public and preserving the right of individual liberty. The enforcement of quarantine, isolation, or the wearing of protective clothing, while it may sometimes be necessary to prevent the spread of disease, is always likely to meet with resistance from people who lack the information, public-spiritedness or trust in government institutions to wish to comply. The San Francisco example of mandatory facemasks has already been mentioned, and there were demonstrations and arrests as a result. Even in wartime, when populations tend to be more willing to cede control to the government, authoritarian impositions (however well intentioned) can often cause resentment and widespread non-compliance. In attempting to control infectious disease outbreaks, public health professionals still have to balance the safety of the many against the rights and liberties of the few. The fact that those most severely affected by communicable disease outbreaks tend to come from the poorest sections of society—as also seems to have been true during the ‘Spanish Flu’ pandemic—while libertarian resistance is more characteristic of wealthier, less-affected populations, only complicates matters further.

Why was the ‘Spanish Flu’ Forgotten?

The gradient of inequality in the impact of ‘Spanish Flu’ has been posited as a reason for the relative lack of attention that historians paid to it for most of the 20th century. Most historians of the last hundred years have lived in the western world and been writing for western audiences, and there are several factors which may have decreased the importance of the pandemic from their (collective) point of view. Firstly, western nations had been the primary antagonists and combatants in the First World War, which was therefore likely to be more prominent in their narratives of the period. Secondly, mortality appears to have been significantly higher in many non-belligerent nations of the global south, where medical infrastructure was weak and death registration systems were generally lacking. The huge death tolls in these impoverished nations mostly escaped the attention of chroniclers of the pandemic until relatively recently, out of a mixture of cultural chauvinism and less easily accessible data. It is worth noting that a 21st century variant of the 1918-19 pandemic would be likely to exhibit an even steeper global inequality gradient in terms of mortality.

For all of these reasons and more, the ‘Spanish Flu’ pandemic remained under-recognized and poorly studied by the medical and scientific community for much of the 20th century. Perhaps this is not surprising. It should be remembered that, although the First World War was, in many of its technologies and tactics, a ‘modern’ war, the medicine of the day was anything but. Doctors of 1914-18 were still operating, and certainly had mostly trained, in a transitional period before the full acceptance of Germ Theory. In 1890, during the Russian influenza pandemic, less than 30 years before the ‘Spanish Flu’ emerged, it was unremarkable for qualified doctors to write to The Lancet that “it must not be forgotten that many unusual earthquakes have occurred during the past year in Eastern Europe. Why should not this troublesome complaint have been produced by injurious emanations from the earth?”. The ‘Spanish Flu’ did little to settle the controversies that were then raging in medical and scientific fields, being enigmatic enough to function as something like a Rorschach Inkblot test, with almost everyone involved in such debates being able to discern support for their own position in its outlines. Arguments over influenza’s causal organism continued largely unaffected and uninformed by the catastrophe.

However, some changes for the better were instituted by those who elected not to deposit the pandemic into the medical memory hole. Legislation enacted in the postwar years added influenza to the growing list of notifiable diseases in many western countries, and also instituted widespread infectious disease monitoring through the International Office of Public Health. Although there was a lack of organized governmental research during the interwar years, private enterprise accomplished a great deal, with the definite identification of the influenza virus finally occurring in the early 1930s. Earlier experimentation with influenza samples had actually been the context in which Alexander Fleming stumbled upon the antibiotic penicillin, a crucial weapon in humanity’s ongoing war against infectious disease. Then, in a distressingly short interval following the so-called ‘war to end all wars’, the poisoned political atmosphere of Europe dragged the continent down into an even greater epoch of bloodshed. And, as is paradoxically but surprisingly often the case, the imperatives of warfare proved to be the spur for scientific developments which would ultimately benefit all of humanity, even though the motive force behind their discoveries was anti-humanitarian by its very nature.

Does War Reduce Resilience?

Despite some positive longer-term outcomes from military interventions (which will be discussed below), war remains a huge challenge to both public health and civil resilience. The technological fruits of armed conflict generally benefit only military personnel during the conflict in which they are invented, and their subsequent usefulness in protecting the health of civilians is always vulnerable to negation by any subsequent war. If the Second World War gave us a mass-produced influenza vaccine then the Syrian Civil War (to take just one example) has prevented it from being used within that conflict zone, as it prevents virtually any systematic vaccination programme from taking place. Despite the massive amount of progress that has been made in the fight against infectious disease over the last century, war remains a significant barrier to the full control of some key diseases, most notably polio. The fact that the risk of a new global pandemic arising from any modern war zone seems to so rarely feature in the political decision-making which determines whether or not nations go to war in the first place, indicates that the lessons of 1918 have not all been well learned. Wars weaken the ability of a country to prevent, detect, or fight outbreaks of infectious disease, and leave the civilian population incredibly vulnerable. The modern ‘failed state’ or warzone remains the most likely crucible from which a new global pandemic might spread.

Does War Improve Resilience?

It was during the Second World War that serious attention began to be paid to the role of the First in causing the greatest pandemic of all time, perhaps for obvious reasons. There was suddenly a pressing need to learn from what was then described as “one of the darkest pages in our medical annals”, and to improve the effectiveness by which the military protected its personnel against infectious diseases, and thereby preserved their fighting strength. Hard lessons learned in military medical units during the First World War were applied and extrapolated, slowly during the interwar years and then rapidly during the Second World War. In 1943, an effective influenza vaccine was finally developed by the U.S. military, which enabled them to dramatically reduce the toll of morbidity and mortality among soldiers living in crowded barracks, which otherwise provide ideal conditions for the spread of respiratory infections.

While warfare in the 20th century killed, disfigured, disabled, and psychologically scarred hundreds of millions of people, it has also been the driver for some of the most valuable medical advancements from which we in the 21st century now benefit. There is some truth, in other words, to the saying that ‘war benefits medicine’, although it is an ongoing discussion if only because medicine certainly benefits more from peace. Whether we consider prostheses, plastic surgery, trauma care, wound closure, or vaccines, the inherent extremis and resources made available to military medicine has meant that it has frequently led the way in terms of technological innovation. Infectious disease continues to be highly relevant in a military context; during the Second World War, more US soldiers in the Pacific Ocean theatre were put out of action by malaria than by combat, and western troops deployed in Afghanistan over the last decade have fallen victim to a wide range of unfamiliar diseases. However, soldiers today are much less likely to be either the initial victims or the vectors of a pandemic (as they were in 1918), because they are among the most comprehensively vaccinated groups in society. The lessons of the ‘Spanish Flu’ pandemic may have been learned to that extent at least.

With the passage of time helping to soothe the collective ego-bruising inflicted by the failures of 1918, the civilian scientific community has overcome their reticence to look too closely at the pandemic, and as a result has made some significant advances. Throughout the latter half of the 20th century there was a gradual increase in attention to the issue, and efforts made to understand the microbiological reasons for the pandemic’s deadliness when compared to seasonal influenza. Informed speculation about some sort of hyper-immune response being at the root of the atypical age-mortality curve, has gradually developed into the ‘cytokine storm’ theory. This concept suggests that an immunological over-reaction, not dissimilar to an anaphylactic allergic response, among those with more robust immune systems (that is, otherwise healthy 20-40 year olds) could possibly explain why those individuals died in higher numbers than the usual casualties of influenza: the very old and the very young. Debates are ongoing about whether the H1N1 variant that produced the 1918 pandemic is more likely to have had avian or swine origins, and this debate has been informed by the development of the important field of veterinary public health medicine, an earlier understanding of which could have potentially helped to prevent many zoonotic disease outbreaks, including the ‘Spanish Flu’.

How Would we Deal with a New Pandemic Today?

Human society’s resilience against a new pandemic, of the sort that the world experienced in 1918, has both increased and decreased. On the positive side, we are now protected by worldwide monitoring and response systems, superior treatment options and a far better understanding of disease processes than were available in the early 20th century. Newer and more effective influenza vaccines are continually being developed and tested. We have antibiotics, thanks in part to Fleming’s careless lab work in the early days of influenza research, which could currently cure many of the otherwise deadly secondary bacterial infections that caused much of the mortality in 1918-19. Policy frameworks such as ‘One World, One Health stress international cooperation and data sharing, endorsing the words of the senior who official quoted as saying that “inadequate surveillance and response capacity in a single country can endanger national populations and public health security of the entire world”. We know far more than the valiant doctors and scientists who battled the ‘Spanish Flu’ pandemic, and no doubt would do a far better job of controlling another 1918-style pandemic, should it happen to reoccur.

On the other hand, we are also vulnerable to the hazards inherent in a far smaller and much more interconnected world than the one in which the ‘Spanish Flu’ pandemic proliferated. Modern air travel would allow an infected person to fly from Europe to Australia in less than a day, meaning that even distant epidemics with relatively short incubation periods are very unlikely to be contained by border-level screening. The 2009 influenza pandemic, caused by a (fortunately) less virulent strain of the H1N1 virus, was a wake-up call for the health protection community, since it exposed the lack of preparedness, the deficiencies in international monitoring, and the difficulties in mounting a coordinated and equitable response to such an event. Officially there were 18,500 laboratory-confirmed deaths, but credible studies have calculated that the total attributable mortality figures for the 2009 pandemic are more likely to be over 280,000 worldwide. And yet these are still relatively small numbers compared to the death toll that a more deadly strain of H1N1 could have caused. In that event, the overwhelming majority of deaths would be likely to occur in the developing world, causing enormous human suffering in countries already beset by political and economic dysfunction.

Conclusion

Resilience requires remembrance, even though remembrance is not always a pleasant or a comfortable task. The ‘Spanish Flu’ pandemic represented a huge defeat for science and medicine, and as such was consigned to a sort of collective cultural amnesia until the subject again became an urgent military necessity. The seeming fact that serious attention to what arguably ought to be the first priority of human civilisation, namely the health of the population, is so often contingent upon the scheduling of hugely destructive wars (and what this tells us about human nature) is probably a subject for another book. However, it is uncontroversial to say that we should attempt to learn from the lessons of history, so as not to repeat them, and this can only happen if the relevant history is remembered. The lessons of the ‘Spanish Flu’ pandemic were largely ignored for many decades, and, to the extent that serious public health concerns are frequently neglected at the expense of military objectives in modern war zones, they are still being ignored, with potentially catastrophic consequences. The Yale historian Timothy Snyder remarks that “History does not repeat, but it does instruct”, yet if policy makers are not paying attention then their ignorance could jeopardize the lives of millions. In the early 20th century, a novel virus was unwittingly spread around the world by human activity, much of it driven by war, and killed so many that we will never truly know the exact numbers. Something similar could happen today. Health professionals in the 21st century would therefore do well to heed this ancestral instruction, and to relay it to our political leaders whenever and wherever they—or perhaps better, being one myself: we—can.