Why is smallpox extinct?
‘Extinct’ simply means there are no reported cases of a disease (or sightings of an animal or plant or bacteria, etc) known for a given amount of time — it does not mean the ‘thing’ in question is permanently or irretrievably gone. The CDC (Center for Disease Control) has arbitrarily set 25 years as the line for declaring a disease extinct. Since there has been no case of smallpox, worldwide, reported in the past 25+ years, it has been declared eradicated (i.e. extinct). However, that said, the small pox virus does still exists in quarantine, in an undisclosed lab someplace in the world. This is necessary for scientific research into combating potential future outbreaks of smallpox (despite their unlikely occurrences) or smallpox-like diseases. Furthermore, with recent advances in genetic engineering, the possibility of someone, one day very soon, having the ability to engineer and sequence the smallpox genome again (or something similar) from common lifeless chemical sources will ine
