Swine Flu war

"Most American casualties of World War 1 came from enemy fire."

In fact some 80% of our casualties came from--the flu, not enemy fire. It was the Great Swine Flu epidemic. According to Bil Bryson's research (in A Short History of Nearly Everything), some military units suffered an 80% mortality rate. "World War 1 killed 21 million people in four years; swine flue did the same in four months."