We had 5 dogs one of our puppies we think just passed due to parvo, He was an outside dog and my daughter saw him throwing up and all other basic symptoms so I went to find him and could not and we found him today 2 days later out in the woods behind our home dead. My question is this how can I prevent my other 4 from getting it? We have 3 inside dogs one that is a year old and 2 that are 8 months old. And one outside that is about 3.