Got some dogs a while back and didn't give em the shots in the correct times, (trying to save money up and do it myself). Seems my yard got contaminated by neighbors dang dog. Lost some really good pups. Already had them baying up some small hogs at 5 months old. Broke my heart when they got it and had to watch them suffer like that. Learned lesson on that deal. Since then I have sprayed bleech on the whole yard and got another pup. She is doing fine but made sure she had shots for about a week before I brought her home...I hope the best of luck to ya, cause losing a dog over Parvo stinks.
PS buy new food and water bowls for all your dogs that shared with the other dog. Not that you don't already know that.