I am so sorry your little one has parvo, and will pray that he recovers.
There was a recent thread about a member who had 2 pups with parvo, and they survived. There is a lot of good information shared in that thread, and one thing is the importance of keeping your pup away from grass, dirt, pet stores, etc. where they can get parvo for well beyond their last vaccinations.
Here is the link:
http://www.yorkietalk.com/forums/sic...ved-parvo.html