I've never quarantined mine, I think there is a type of ramshorn that carries a parasite, but I think that is more focused on wild caught snails. Not snails that have been transferred from businesses/breeders to other businesses/breeders.
You could for safe measures. I don't quarantine any of my inverts or snails before putting them in, just do the drip bag getting them used to the water before dumping them in.
