Protecting a Vaccinated Dog from Parvo

First thing, only puppies get parvo. So if you don't have a puppy, there's nothing to worry about.

And get your dogs immune system up. I would see a homeopath. Curcuminoids are excellent anti-oxidants. Colloidal silver is good. Willards water is also good. All of them.

If your dog goes outside and you think the infected dog gets in your dogs space you can spray the area with bleach. You might also call a vet and ask them for some advice.