I want to put snap together wood flooring over bathroom subfloor. Is this effective?
There's a lot of problems with this


particle board subfloor
snap-in wood flooring
bathroom flooring


Your bathroom is a wet zone. Wood floor/subfloor and water don't go together. Add in


  Due to water damage I needed to repair a section of my particle board bathroom subfloor


and you have a recipe for disaster. The water will penetrate a wood floor and wreck your wood subfloor again. What you need here is


Waterproof membrane. Could be a vapor barrier, but could also be something like waterproof cement board or polyethylene underlayment. Make sure to use an approved method to seal the seams. You do NOT want to have to tear the floor up to repair subfloor.
Waterproof flooring. Tile used to be the only product here, but floating floor vinyl has become more common on the market. Because it's 100% vinyl, it won't be harmed by water, and it goes down like any other floating floor. Do not use wood flooring in a bathroom (especially solid hardwood), as these floorings respond poorly to repeated water exposure.