What other virus entered with the others, but was not easily detected in osmosis Jones.

The virus Thrax entered with the other.

Explanation:

In the movie, Osmosis Jones, Thrax enters the body of Frank DeTorre, an obese widower without any iota of regard for hygiene and health, when the man ate an egg that was spat by a monkey on to a muddy floor. Thrax was able to infiltrate the City of Frank, a huge metropolis inside the body of the man, in which each cell is living a life similar to that of humans, with white blood cells as the police and germs as criminals.

i think the answer is strength