Centennial of a Pandemic: The 1918 Flu

It’s 1918, and the First World War is beginning to wind down across Europe. But another scourge is also spreading, and it will eventually take even more lives. It's influenza – or the flu – an adversary that’s still with us a century later. It returns, ever changing, each year, challenging us to create a matching vaccine and prevent another pandemic. As we enter the annual “flu season,” a look back at the 1918 flu is a potent reminder that influenza is not just a bad cold. It is, in fact, a deadly disease, and immunization is still our best weapon in this medical hundred-year war. Here are 10 amazing facts about the 1918 flu pandemic:

1. It was not Spanish: The 1918 flu pandemic is sometimes called “The Spanish Flu,” but it was not Spanish in origin at all.  Spain remained neutral during WWI and freely reported on the growing epidemic, thus the flu became associated with Spain. The nations involved in the war, including the U.S., initially suppressed news about it fearing it would hurt morale and cause additional distress.
2. War helped it spread: The flu was, in part, a product of the war, because close quarters and massive troop movements helped it spread. In the United States, the first heightened flu activity appeared in military bases in the spring of 1918, shortly after the U.S. entered the war in 1917.
3. Three waves: The pandemic flu came in three waves. The first wave, in spring 1918, was the mildest and the second wave, which began in September, was the most severe, killing 100,000 in the U.S. in October alone. The third and final wave began in early 1919 and ran through spring, causing yet more illness and death.
4. By the numbers: The 1918 flu is often called the deadliest pandemic in history. It is estimated that about 500 million people or one-third of the world’s population became infected and at least 50 million people worldwide died from the flu and its complications, like pneumonia. In the U.S. one in every 153 people died. In comparison, approximately 16 million people worldwide died during the war. The high mortality in healthy people, including those in the 20-40-year age group, was an unusual feature of this pandemic.
5. Life expectancy: In the U.S., the flu caused about 675,000 deaths. This was enough to cause the average life expectancy in America to temporarily drop to 48 years for women and 42 years for men – a drop of 12 years. 
6. Battling the flu: In 1918, the tools to fight the pandemic were limited. Viruses had not yet been identified, there were no vaccines to protect against the flu, no antivirals to reduce symptoms, and no antibiotics to treat complications like bacterial pneumonia. Control efforts worldwide were limited to methods such as quarantine, hygiene, use of disinfectants, and limits on public gatherings.
7. The American Lung Association joined the fight: The impact of the epidemic was so great that the National Tuberculosis Association (later to become the American Lung Association) temporarily added influenza to many of its public health campaigns, teaching people how to help stop the spread of both tuberculosis and the flu.
8. A familiar foe: Today, scientists know this pandemic was caused by an H1N1 virus, a strain that remained as the dominant seasonal flu for the next 38 years. It’s still with us, in a way, because the H1N1 strain that triggered a pandemic in 2009 was a distant relative of the 1918 strain.
9. Finally sequenced: The genome of the 1918 virus was fully sequenced in 2005. Although we have unlocked its DNA, scientists still don’t fully understand what made this particular strain so deadly.
10. Preventing the next pandemic: The science of preventing and treating the flu have come a long way in the last 100 years. Because the flu mutates every year, a different vaccine must be formulated, manufactured and distributed worldwide every year. While the vaccine is more effective some years than others, the annual flu vaccine is recommended by the Centers for Disease and Control and Prevention (CDC) for everyone 6 months and older.

The American Lung Association has more tools and tips on how to protect yourself and those around you from the flu. And one final tip – the annual flu vaccine usually becomes available each September. So why wait? Get vaccinated now and make sure your loved ones do to!