watch 02:03 Wiki Targeted (Entertainment) Do you like this video? Play Sound Pathogen was a microorganism that carried a disease. At some point in the 2020s, Adam Lang's bloodstream had been infected with an alien pathogen. It was later identified as Praxeus. (TV: Praxeus) Retrieved from "https://tardis.fandom.com/wiki/Pathogen?oldid=2997720" Categories: Biology from the real world Microorganisms + cat Cancel Save Community content is available under CC-BY-SA unless otherwise noted.