One of the most devastating public health crises in history hit the U.S. on this date 97 years ago — and experts are still studying it, hoping to head off a similar global pandemic. The first cases of what was called “Spanish flu” were reported among soldiers at Fort Riley, Kansas. By October, the worst month, 195,000 Americans perished. By 1920, nearly one-in-four Americans had suffered from this strain of the flu, killing about 600,000. Worldwide, estimates put the death toll up at 50 million or more. Even less dramatic strains of flu can be deadly, necessitating medical research. There are some 112,000 medical scientists and 6,700 medical laboratories in the U.S. today. The output helps America’s 737,000 physicians and surgeons in maintaining our health. Profile America is in its 18th year as a public service of the U.S. Census Bureau.