A flu that killed a hundred million people

Caught between the great epidemics of the past and the horror of the world war, the 1918-1919 flu has long struggled to be recognized as a major health and social disaster. Reactions to the current epidemic reflect a recurring denial of a disconcerting disease.

A few days before dying from the scourge that ravaged the world in 1918, Guillaume Apollinaire still found the strength to be ironic about this “worldly” flu contracted by the King of Spain, Alphonse XIII : “Without yet singing victory, we can now envisage the end of the epidemic. (…) The Spanish flu will be nothing more than a bad memory.” Weakened by a war wound, the poet succumbed on November 9, while the number of victims of what was now called, in the French and English-speaking press, the “Spanish flu” exploded.

This is an irrelevant name because, although the flu was virulent in Spain in the spring of 1918, its origins were probably elsewhere, in the American Midwest. Zoonosis, i.e. an infectious disease transmitted from vertebrate animals (especially birds, pigs and cattle) to humans, the 1918-1919 flu already belonged to the type H1N1made famous in 2009 by an eruption that caused global concern. The driving forces of globalization and the particular context of the end of the First World War explain its rapid circulation, over almost two years, across the entire planet, making it the first truly global pandemic and leaving between 50 and 100 million victims.

The book devoted in 2018 by the health historian Freddy Vinet to this flu traces the issues of a disease whose scale even contemporaries had difficulty grasping. He underlines the difficulty in “thinking about the flu”, while the Pasteurian revolution seemed to triumph over major epidemics and the world conflict focused attention with its bloody harvests. This disbelief is all the greater because, while the flu hits social classes and ethnic groups very unequally, in Europe it mows down what remains of a young generation very tried by the war.

Three deadly waves

If the flu was confusing at the time, it was because it struck in three waves – the timing of which varied marginally depending on the region of the world. Between April and July 1918, a first wave in France was accompanied by high morbidity, particularly in the garrisons, but the mortality rate remained relatively low. The feeling of a decline in the summer was misleading, because a second wave began in August-September, when fatal lung infections multiplied. Up to a third of the population was struck by the disease, while many of the youngest patients died. Mortality peaked in the 25-34 age group, which caused consternation among doctors. At the beginning of 1919, a third wave again led to high morbidity, but a lower number of deaths.

Beyond the global analysis of the pandemic, Freddy Vinet underlines the functioning of the infection in “bursts” in a local context. In rural France, the epidemic rarely hits the same village for more than two weeks and only lasts long in large cities (pp. 34-35). Suddenly, military units find themselves incapacitated, like the British fleet which has to reduce its sorties in May 1918, because 10% of its personnel are missing. These outbreaks overflow the health services already tested by the war, as a deputy noted in the Chamber on February 18, 1919: “There are currently a very large number of sick people suffering from influenza pneumonia; many are dying for lack of care, for lack of doctors” (p. 32).

Just as important as the aspects that the historian keeps track of, there are those that escape him, due to lack of sources or attention. The newspapers report that President Wilson and Clemenceau had to briefly take to their beds, but little is known about the servants in the West of Paris, who increased the excess mortality in these wealthy neighborhoods. Even less well known is the fate of the working classes and blacks in the United States (pp. 100-102). As for the Asian populations – particularly Indians – or Middle Easterners, their fate remains largely unknown, which explains the variations in the epidemic’s toll. One figure gives an idea of ​​the discrepancy: while the flu killed 240,000 people in France, there were probably more than 4 million deaths on the island of Java, which has an equivalent population (pp. 71-72).

The disarray of societies…

Beyond these geographical variations, the book shows how influenza occurs at the wrong time, in light of the canonical history of medicine. For a long time, medicine tended to present the Pasteur revolution as the beginning of a triumphant march against infectious diseases, putting an end to the “blue fear” that cholera had created in XIXe century. True, the plague struck again with resounding force in Manchuria in 1910-1911 and the flu itself had a virulent episode in 1889-1890, but the disease no longer seemed to correspond to its times. Doctors were disoriented, which fueled the erratic search for miracle cures by the population.

Looking back does not remove all the uncertainties. We now know the type of virus and we can describe the contagion of this flu, but there is no consensus on the elements relating to possible mutations of the virus and the role of environmental factors. Although the process of contagion was already known at the time, the search for climatic or meteorological determinants continued to preoccupy contemporaries, while comments on predispositions and comorbidities increased. The pneumococci that cause lung infections thus attack people who are already weakened, for example by war gases.

The contradictory signals given by the epidemic during its different waves add to this confusion and explain the initially reassuring words of the doctors. Journal of Practical Medicine and Surgery can thus write, on September 10, 1918 – on the eve of the second wave: “Influenza is a relatively minor illness, for which quarantine or disinfection measures at the borders applicable to other diseases would be unjustified and moreover useless” (p. 113). A few weeks later, the tone changes completely.

…and the “government’s bluster”

Censorship and self-censorship of the press of the belligerent countries explain why, until the autumn of 1918, no one dared to give much importance to the flu. The military doctors themselves, on the front line of vigilance and producers of valuable reports to analyse the epidemic, could not neglect the demands of the war effort. In contrast, the Spanish press largely mentioned the epidemic, which gave credence to the idea of ​​a Hispanic origin of the virus. This disorientation reflects the difficulty in locating the circuits of the epidemic in a globalised economy: the time of the “oriental plagues”, which could be contained by a mixture of targeted quarantines and health mechanisms, was over.

It is hardly surprising, therefore, that the measures taken by the authorities of the various countries are struggling to cope with the health catastrophe. They do not want to close the borders, so as not to block war supplies, and they do not dare to take too drastic measures against economic, cultural and social life, so as not to aggravate the consequences of the war. Prophylactic measures are only rarely applied on a national scale, and local authorities are given the “unpleasant privilege (…) of taking unpopular measures to control the spread as much as possible” (p. 112).

This weak reaction is a reminder that political, diplomatic and social factors in the measures taken often weigh more than medical and health considerations. The lack of medical and nursing staff, as well as the shortage of equipment, hinder the satisfactory management of the sick in all the affected areas. At the same time, there is procrastination over the closure of schools, places of entertainment and gatherings and the population hardly takes ownership of the prophylactic measures. It is finally the growing absenteeism that will force a review of the operating rules, as in the Paris metro which sees its traffic greatly reduced in October 1918.

In view of the health disaster that it constitutes on a global scale, the great flu leaves only a faint trace in memories, for want of being able to “resonate” with the rest of the world. XXe century: if its name remains proverbial, its underlying realities fade away. Its diffuse chronology does not lend itself to the canonical description of major catastrophes and it is ultimately its banality, difficult to distinguish from seasonal flu, which erases this “invisible enemy” in favor of older major epidemics. In addition to the low interest of medical history until the 1980s in this episode, the work rightly recalls the bad conscience of a generation that preferred to glorify the death of its children in war rather than from the flu, even if it meant hiding “its negligence and helplessness during this episode” (p. 178-179).

But isn’t it also the political aspect of this episode that explains its uncertain memory? Freddy Vinet’s work indeed echoes the questions about the ability of liberal regimes to respond to the epidemiological challenge, in line with the American historian Alfred W. Crosby who noted that, “during an epidemic, democracy can be a dangerous form of government”. The carelessness of the French population during 1918 here echoes in a disturbing way the disorientation it manifests at the beginning of 2020.

If the Covid-19 epidemic reminds us that the “return of epidemics” concerns Europe as much as other regions of the world, despite considerable progress in medicine and virology, it is above all testing the capacity of societies to react to a collective and intuitively elusive threat. It is indeed the enormous gap in “epidemiological cultures” (p. 204), nourished by immediate or more distant history, that is revealed on the eve of spring when our world finds itself, once again, seized.