Vaccines have saved more lives than any other medical intervention throughout human history by preventing the spread of infectious diseases. Experts credit vaccines with preventing an estimated 6 million annual deaths worldwide. Perhaps the greatest vaccine success story is that of the eradication of the smallpox disease, which is believed to have killed approximately 300 million people between
1900 and 1977, while disfiguring and blinding millions more. For perspective, that is more lives lost than the combined death toll of both world wars.
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