One common admonition on handling bass is that we are damaging their protective slime coating when held in dry hands.

If frequently handled bass caught a fatal infection, would that manifest as obvious lesions or damage on their exterior, or is there a chance that an external pathogen reached their bloodstream and did interior injury?

(I have no clue as to the answer, just trying to learn more about how handling the fish causes stress, and/or injury or death.)