Smallpox was an infectious viral disease infecting humans from around 10,000BC until 1979, when the World Health Organisation confirmed its eradication. The virus finds its way into the small blood vessels of the skin, causing a rash and flu-like symptoms, then fluid-filled blisters which erupt across the body. The more serious strain of smallpox has a mortality rate of 30-35% and the survivors are commonly left with scars on the face and sometimes blindness. The disease was airborne and very contagious – in the late 18th century it was estimated that around 400,000 Europeans died from it every year, and in the 20th century it caused between 300 and 500 million deaths worldwide. Vaccination programmes were carried out in the 19th and 20th centuries, controlling outbreaks by vaccinating all those in the area and then eventually making smallpox innoculation mandatory (these injections were stopped in 1980). The WHO was able to confirm its eradication in 1979 and all specimens of the virus have been destroyed or moved to secure laboratories for research purposes.