Plague, and the infamous Black Death, spread quickly for centuries, killing millions. Plague still occurs but can be treated with antibiotics.

Add Yahoo as a preferred source to see more of our stories on Google. Just south of Tucson, sits one of the last boomtowns of the American West. Tombstone, nicknamed "the town too tough to die," is ...

Just south of Tucson, sits one of the last boomtowns of the American West. Tombstone, nicknamed "the town too tough to die," is chock-full of Wild West lore and historic landmarks. Whether you're ...