Bacteria on the lens

Technically you have mold (fungi) eating the lens coatings. A good dose of UV to kill the growth is about all you can do unless you take the lens apart to replace the effected lens. Lens fungus & Does UV Light Kill Candida Auris?

Why you think cleaning would work, the lenes coatings are now eaten so washing the lens might wash away the mold the damage coating will still be present. With the proper solvent and polish you could strip the coatings off fully, but then the image quality will suffer. That still leaves alignment and not damaging things in the process.

To prevent this you need to store your gear in less humidity and make sure it’s not damp when storing.