Old parvo, new puppies?

Hello vets/techs! What's the actual chance of a puppy catching parvo in a house thats had it? Do they need to eat old infected poop? Walk on ground that might have had some infected poop in the area? Or just breathing the same air?? (Little facetious there) i got 2 small breed puppies they've had their first 4 in 1 and been dewormed (was told every 3 wks for vaccines then weekly for worms for 2wks, they had visible hookworms.) I've been keeping them in a spot never visited by dogs (or people really) in the back basement room, they're locked in a crate with a space for them to go potty. My plan was to keep them crated till they've had all their shots. Is it really likely if they came upstairs they'd end up catching it? Or better to err on the side of caution and keep them downstairs?

Hello - thats a very good question and I cannot find a good answer; indeed it's my beleif that a maximum time period for the survival of Canine Parvovirus in the environment may not be widely known (due to lack of research).  What is known is that Parvovirus can survive for months, even years and that it does so by clinging to small bits of organic material, including those in furnishings, soil and so on.  Your vet can advise you on disinfection, which needs to be done with disinfectants specific to viruses and can be effective for wipe-clean surfaces.  However soil, sand and other organic matter (eg in your garden) as well as soft furnishings are harder to clean.  Your vet can help to advise you about how best to do this but it's certainly safest to have a puppy vaccinated before bringing it back to your house wherever possible.