It is unknown how many people died of smallpox in the 3,000 years it has likely infected humans, but it has been estimated in the 20th century alone to have killed more than 300 million people. How do you fight something that terrible and seemingly unstoppable? In hindsight, the answer seems pretty straightforward: Start with … Continue reading Rev. Cotton Mather and the 18th-Century Battle Over Smallpox Inoculation