Parvo ?

For one you cant have had parvo for a while with out noticing the signs..vomiting diareha-nasty smelling, weight loss, dehydration,loss of appatite, leathragy...if anything I'd ask them what dog food they gave him or if he ate something weird, etc...the pup should have had all its shots by 5 months..what can you do? well just keep watch of your other dogs. if your real worried put some space between the dogs to prevent cross contamination, but if the dogs have had there shots then there shouldnt be a problem.