Pox is a Furon who led the Furon Invasion of Earth in the 1950s - one that was established through their race's psycic powers. He established Cryptosporidium as President of the United States and harvested Human Brains to create pure Furon DNA in order to save his species. He even created a version of Cryptosporidium, Cryptosporidium-138, who had working genetalia. Woohoo!
The only problem was, the KGB didn't like this nonsense and blew up the Furon Mothership, killing Pox. However, he was able to download a copy of his personality into a HoloPox and continue his existence that way, helping Cryptosporidium to destroy the KGB and their allies, the Blisk.