The deadliest period in human history. When do you suppose this might have been? The Second World War? Nope. The Black Plague? Not even close.
No, the deadliest period in human history is one you're not likely to see mentioned in your high school history books: the 1918 flu pandemic. The months of September through December of 1918 comprised the period of the highest intensity of a disease that spread throughout the world over the course of the year. First appearing in the spring as a fairly "normal" influenza remarkable in its virulence if not its mortality, it returned in September, reborn in a truly lethal incarnation, and unleashed itself on the world as if it were Nature's own vengeance.
The most conservative estimates claim that 20 million people died in the event, and recent studies suggest the death toll may have been between 50 to 100 million. If we accept even the most conservative estimate, this pandemic took the lives of nearly five million people each month, a mortality rate that outpaces even the darkest days of the Second World War. The global population at the time was around 1.8 billion, meaning between 1 to 5 percent of the population died from influenza in that year.
Perhaps the horror can be best illustrated by our national life expectancy at the time: in 1917, our life expectancy was 50.9 years; by 1918, it had dropped to 39.1.
It was influenza — only influenza — and the misguided patriotism of the era kept it out of the newspapers. Because of such "patriotic" censorship, most thought the influenza was a local or regional disaster and very few realized the disease was ravaging not only families and communities but the entire nation. In a time when men were jailed for simply suggesting that Germans "weren't such bad people," it was thought unpatriotic to publicly address these health concerns. It would have been considered "fear-mongering," so much so that not once did President Wilson mention it in public, even as it tore through every corner of the nation.
Many stories have surfaced of the horror of the pandemic: bodies stacked like cordwood; horse-carts picking up bodies off the streets; cities in which gatherings of people were banned; a mother too weak to move to even feed her newborn twins as the decomposing body of her husband lay in a bed across the room. A good friend of mine recently told me that three of his grandmother's brothers had died in the same week from the flu.
In India and Africa, some have estimated the pandemic claimed as much as five percent of the total population. In American Samoa, 20 percent of the population was lost. In some Inuit villages in Alaska, the pandemic killed over 70 percent of the population. One can only imagine what the death toll must have been like among the uncounted millions in China, then wracked by internal strife.
The 1918 pandemic was no ordinary influenza. Unlike almost all other forms, this was not only a grave threat to the old and frail and very young, but rather most deadly to those whose immune systems were the strongest. The incubation period lasted at least a week without major symptoms which led to its incredible worldwide virulence, and once symptoms began appearing the virus worked with tremendous speed. The first symptoms were what we would consider normal today, but would worsen to the point that the patient would begin to have difficulty breathing. Extremities would turn blue from lack of oxygen (a process called "cyanosis") to the point at which the victim's race became difficult to determine.
This cyanosis was caused by a reaction known as a "cytokine storm," in which the body's immune system kicks into overdrive and sends every available antibody to the lungs, often leading to the patient drowning in his or her own bodily fluids. These cytokine storms were ironically deadliest to those with the most powerful immune systems, as those who were "healthier" would have a stronger response to the virus and thus a more deadly cytokine storm. Today this occurrence is known as Severe Acute Respiratory Syndrome, or SARS.
I call myself an amateur historian, but this event illustrates how much I have left to learn. I had heard of the Spanish Flu Epidemic of 1918, but it wasn't until less than ten years ago that I began to realize the scale of this event and why the World Health Organization has been so afraid of another pandemic. It is accepted in the virologist community that a pandemic similar to the 1918 outbreak will happen again, it's only a matter of time. It makes sense that every major health organization watches intently not only for clusters of deaths to SARS, but also mass avian epidemics — especially poultry — as all influenza originates from birds. All influenza is essentially "avian flu."
The modern threat is both lesser and greater, for while we have a far greater public awareness of health care and the media can spread news of an outbreak at light speed, the world's population is also far more mobile that ever before. Travel times have decreased from weeks or months for intercontinental travel to 24 hours at most, thus greatly magnifying the threat of any disease with a long incubation period.
I found some reassurance when my passport arrived a week ago. In a pamphlet of information included with my passport were three warnings: one concerning required actions for a lost or stolen passport, another warning about the necessity of being aware of potential terrorist threats, and the last giving strong recommendations in the event of a pandemic. At least in the modern era our government is prepared to lead and and use every tool at its disposal to minimize the danger, unlike ninety years ago when the acknowledgment of the deaths of tens of thousands of Americans each week could be considered unpatriotic.