Thrax is the main antagonist of the 2001 film Osmosis Jones. He is a virus who happens to be here, presumably from Frank, the character in whose body the animated part takes place, eating a boiled egg with mayonnaise, that was covered in monkey saliva and has falling on the floor, eaten 10 seconds later, much to the disgust and concern of his daughter Shane. He plans on killing Frank and then Shane afterwards.
He was voiced by Laurence Fishburne.