Trivia: Thrax is like Morpheous from the Matrix trilogy. His black coat, black glasses and he is even voiced by Laurence Fishburne. In his end fight with Osmosis there is a very clear Matrix reference (the bullettime effect).
Trivia: In the widely released version of Osmosis Jones in the background of the opening chase scene, a remix of Foreigner's 'Hot Blooded' plays, but in the VHS release it plays Electric Avenue by Eddy Grant.
Trivia: Originally there was going to be a toy line made for Osmosis Jones, but WB lost faith in the project and canceled their release. Only prototypes of the toys exist today.
Answer: We are never told that the monkey was sick with the disease. The egg does fall out of the monkeys mouth and onto the ground where the virus could have easily been on the ground and it just happened to come into contact with the egg.