I came into the world just after the polio vaccine had been introduced. Polio was something we heard about from our parents, who had vivid memories of being kept indoors as children because of polio outbreaks. There was a man in my school, a counselor named Mr. Nichols, who was crippled in one arm - it was small, like a child's, and he could not use it - from having had polio as a boy.
Before polio, there was the Spanish Flu. It got its name because it broke out near the end of the Great War, and most of the belligerents in WWI had imposed wartime censorship on their presses. Only in neutral Spain could news of the influenza epidemic be read. We still call it the Spanish flu for convenience, not because anybody hates Spain, but because "Spanish flu" is a lot easier to say than "nineteen eighteen influenza epidemic".
And there was dysentery, familiar to us only from the Oregon Trail video game. And cholera, smallpox, and (farther back in history) bubonic plague. And it's amazing to me that, growing up in the 1960s and 70s, I lived a childhood blessedly unscathed by outbreaks of serious infectious diseases.
Something to ponder, while sheltering in place and practicing social distancing.