Memory Beta, non-canon Star Trek Wiki
Memory Beta, non-canon Star Trek Wiki

Virillian toxic fever was a disease which the science officer of the USS Enterprise was struck down with shortly before the starship was due to begin a long term survey of the Pathiad Nebulatae.

History and specifics[]

The toxic fever affected the officer to such a degree that Captain Pike enlisted Cadet Spock to take on the science officer's role. (EV comic: "Flesh of My Flesh")

Presumably the descriptor "Virillian" refers to a race or culture, or possibly a location such as a planet or planetoid.