Smallpox is a deadly virus that is eradicated (no longer in existence). Smallpox was responsible for the deaths of hundreds of millions of people in the second millennium alone. Smallpox was characterized by the eruption of hundreds or thousands of fluid-filled blisters on the skin of an infected person as well as high fever, blood poisoning, and organ failure. Scientists believe Smallpox was born as an animal infection that crossed over to humans. Because Europeans often lived in close proximity to livestock and to each other, viruses such as smallpox, measles, and influenza were able to proliferate and spread rapidly. These diseases were (and are) highly contagious and quickly overwhelmed pockets of people living in close proximity to each other. In Europe, those who survived acquired antibodies and immunities that were passed on to future generations, which decreased the virulence of such viruses in certain areas.
Smallpox became established in Europe in the 1500’s during the Crusades, when the population of the continent increased, and when the population became more mobile. Periodic outbreaks of Smallpox in Europe and Asia would scar millions and cause the deaths of as many as 30% of the children who contracted it. Smallpox was non-existent in the western hemisphere until European explorers introduced it. Smallpox was likely first introduced to the New World when a Spanish sailing ship landed on the island Cuba in 1520. It was then when the first documented cases of Smallpox emerged among native populations.
Smallpox devastated populations of Native Americans, who had no resistance, and was a major cause of the collapse of the Aztec and Empire in Mexico and the Incan Empire in South America, as well as many other native empires. It is thought that European conquistadors may have used Smallpox as a weapon in their conquests of native peoples. Smallpox quickly spread through the Native populations in the New World. As many as 90% of Native Americans who died during the Age of Exploration and New World settlement, died of Smallpox and other diseases brought by European explorers and settlers, making disease the single greatest factor contributing to the collapse of native tribes and empires.