Bathroom Mold Growing on Walls

My parents live in Southern California. About three years ago they tore down the wallpaper in their bathroom because they were going to remodel, but never actually got around to doing anything so the walls are just exposed drywall.

I went home for a visit (I live across the country) and was stunned to find that two of the bathroom walls were now growing mold... a lot of it. Obviously this has been an on going problem that they've never bothered to do anything about.

I am worried about the health risk. I can install a new ceiling fan to improve the ventilation, but can I kill the mold so it won't grow back, without tearing out the dry wall? Once, I've cleaned the mold off the surface of the walls is there a paint that I can apply to keep it from growing again?

I'd appreciate any advice.

 

im guessing you mean exhaust fan in the bathroom? you need a fan rated for double the sq footage

it all depends on why the mold is there...if its just suface mold from moisture from a shower...cleaning it off with a cleaner rated for killing mold...keyword..it is rated for it...not just cleaning it...most think bleach does...but i do not believe it is rated for it...a product called microban will ....only after the gross amount of the mold has been precleaned

if the problem is so bad that is just all over the place or the drywall has become mushy....i would consider ripping it out

after cleaning drywall if you can....sealing with an oil based shellac or primer...a decent semi gloss paint will help keep the moisture out of the drywall