From September through November of 1918, the death rate from the Spanish flu skyrocketed. In the United States alone, 195,000 Americans died from the Spanish flu in just the month of October. And unlike a normal seasonal flu, which mostly claims victims among the very young and very old, the second wave of the Spanish flu exhibited what’s called a “W curve”—high numbers of deaths among the young and old, but also a huge spike in the middle composed of otherwise healthy 25- to 35-year-olds in the prime of their life.
“That really freaked out the medical establishment, that there was this atypical spike in the middle of the W,” says Harris.
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Not only was it shocking that healthy young men and women were dying by the millions worldwide, but it was also how they were dying. Struck with blistering fevers, nasal hemorrhaging and pneumonia, the patients would drown in their own fluid-filled lungs.
Only decades later were scientists able to explain the phenomenon now known as “cytokine explosion.” When the human body is being attacked by a virus, the immune system sends messenger proteins called cytokines to promote helpful inflammation. But some strains of the flu, particularly the H1N1 strain responsible for the Spanish flu outbreak, can trigger a dangerous immune overreaction in healthy individuals. In those cases, the body is overloaded with cytokines leading to severe inflammation and the fatal buildup of fluid in the lungs.
British military doctors conducting autopsies on soldiers killed by this second wave of the Spanish flu described the heavy damage to the lungs as akin to the effects of chemical warfare.
Harris believes that the rapid spread of Spanish flu in the fall of 1918 was at least partially to blame on public health officials unwilling to impose quarantines during wartime. In Britain, for example, a government official named Arthur Newsholme knew full well that a strict civilian lockdown was the best way to fight the spread of the highly contagious disease. But he wouldn’t risk crippling the war effort by keeping munitions factory workers and other civilians home.
According to Harris’s research, Newsholme concluded that “the relentless needs of warfare justified incurring [the] risk of spreading infection” and encouraged Britons to simply “carry on” during the pandemic.
The public health response to the crisis in the United States was further hampered by a severe nursing shortage as thousands of nurses had been deployed to military camps and the front lines. The shortage was worsened by the American Red Cross’s refusal to use trained African American nurses until the worst of the pandemic had already passed.
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But one of the chief reasons that the Spanish flu claimed so many lives in 1918 was that science simply didn’t have the tools to develop a vaccine for the virus. Microscopes couldn’t even see something as incredibly small as a virus until the 1930s. Instead, top medical professionals in 1918 were convinced that the flu was caused by a bacterium nicknamed “Pfeiffer’s bacillus.”
After a global flu outbreak in 1890, a German physician named Richard Pfeiffer found that all of his infected patients carried a particular strain of bacteria he called H. influenzae. When the Spanish flu pandemic hit, scientists were intent on finding a cure for Pfeiffer’s bacillus. Millions of dollars were invested in state-of-the-art labs to develop techniques for testing for and treating H. influenzae, all of it for naught.
“This was a huge distraction for medical science,” says Harris.
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By December 1918, the deadly second wave of the Spanish flu had finally passed, but the pandemic was far from over. A third wave erupted in Australia in January 1919 and eventually worked its way back to Europe and the United States. It’s believed that President Woodrow Wilson contracted the Spanish flu during the World War I peace negotiations in Paris in April 1919.
The mortality rate of the third wave was just as high as the second wave, but the end of the war in November 1918 removed the conditions that allowed the disease to spread so far and so quickly. Global deaths from the third wave, while still in the millions, paled in comparison to the apocalyptic losses during the second wave.
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