Influenza does not rate with the public as a terrifying disease. One might start a panic any time by shouting “smallpox!” or “yellow fever!” in a crowd, but can you picture any considerable number of people running from “the flu”? The term has a frivolous, almost comical connotation, quite in contrast with the fearsome images invoked by such portentous words as “Asiatic cholera,” “typhus,” and “plague.” It would be mere posturing to belittle the history of these scourges, but one may fairly question whether in the long roll of the centuries any of them outranks epidemic influenza as a killer. From the first recorded outbreak, the Greek pestilence of 412 b.c. mentioned by Hippocrates and Livy, which many students of medical history identify with this disease, through to the world pandemic of 1918, influenza has sporadically flared up with explosive suddenness, prostrating unusually large numbers of the population, destroying many victims directly, and laying others open to additional infections which complete what influenza began.
Indeed, it is doubtful that any other communicable disease ever infested so many lands and involved so many human beings at one time as were stricken by influenza during 1918 and 1919. There was a mild outbreak in the spring of 1918, but beginning in the fall a most virulent form of this epidemic literally girdled the earth within a few months, touching every continent and most of the inhabited islands of the sea, causing hundreds of millions of people to become ill, and killing more than twenty millions. In the United States, 548,452 deaths from influenza occurred over the ten months beginning with October 1918. Even the overworked physicians fell prey, for the records of the American Medical Association for 1918 show a rapid increase in the number of its members dying of influenza and pneumonia. The death rate in several European countries exceeded that of the United States, and in Asia it was still higher. India’s toll has been estimated at more than 12 million dead. Steamships carried the infection across seas and oceans. Thus the Demerara from Lisbon touched at Rio de Janeiro on September 17, proceeded to Montevideo, and on the twenty-fifth reached Buenos Aires; influenza broke out in each of these cities within a few days of the ship’s arrival.
In Java and Madura in the Dutch East Indies, the deaths from influenza for the single month of November numbered 402,163, whereas the combined death roll from cholera, smallpox, and the bubonic plague totaled only 11,598 for the entire year of 1918. Spots of Africa were stricken: a British colonial officer visiting a remote Central African region found “villages of 300 to 500 families completely wiped out, the houses having fallen in on the unburied dead, and the jungle having crept in within two months, obliterating whole settlements.” Far out in the Pacific the steamship Talune, from Auckland, visited British Samoa on November 7; before January, 8,000 deaths had occurred in two of its islands. In Tahiti, one seventh of the 4,500 inhabitants died between November 25 and December 10, while “day and night trucks rumbled through the streets, filled with bodies for the constantly burning pyres.” Dr. Edwin O. Jordan of the University of Chicago, from whose careful survey the foregoing figures are taken, says that the 1918 epidemic “affected nearly every family on the civilized globe.”
All this happened little more than twenty years ago, and it is only because of the overshadowing human interest in the World War, which was rushing to its climax in those same fateful weeks, that we forgot or were oblivious to the vaster depredation of the epidemic, which wiped out more human lives than the War did.
Devastating diseases almost invariably come in the troughs of wars, famines, political and economic collapses, and other violent upheavals of society. Historians have pointed to a correlation between the outbreak of the plague in Justinian’s time and the fall of the Roman Empire. Similarly it has been suggested that the plague that overswept Europe in the fourteenth century marked the breakup of medievalism and harrowed the ground for modern civilization. There were destructive epidemics in the early nineteenth century, following the Napoleonic Wars. Great waves of influenza troubled Europe and America in the 1830s. Other influenza pandemics followed, in 1847 and 1889, and then after three decades of quiescence came the vast outburst of 1918, which showed what influenza can do on a truly global scale, with not merely a continent but the whole planet as the stage of its action. In the present state of international and economic affairs one cannot but wonder what pestilence we may get from another world war — or as the aftermath of a prolonged period of mass anxiety.
Whatever the political future, we may be sure that we are not done with influenza. It is always with us, usually in scattered cases and in a form more mild than its pandemic variety; but always there is a possibility that a change in the strain of the infective agent, or a lowering in the resistance of the population, will provide the spark for another worldwide explosion.
From an essay published in the January 1940 issue of Harper’s Magazine, one of more than a dozen pieces on science and technology Gray wrote for the magazine. The complete essay — along with the magazine’s entire 164-year archive — is available here.