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The first documented use of surgical anesthesia in the United States was in Connecticut in 1844.
Bacteria have flourished on the earth for over three billion years. They were the first life forms on the planet.
Cancer has been around as long as humankind, but only in the second half of the twentieth century did the number of cancer cases explode.
Only one in 10 cancer deaths is caused by the primary tumor. The vast majority of cancer mortality is caused by cells breaking away from the main tumor and metastasizing to other parts of the body, such as the brain, bones, or liver.
Vaccines cause herd immunity. If the majority of people in a community have been vaccinated against a disease, an unvaccinated person is less likely to get the disease since others are less likely to become sick from it and spread the disease.