First of all, it is important to understand that puppies that have not received all their shots are not fully protected from infectious disease, especially parvovirus (even those puppies that HAVE indeed received their full series of vaccines are still susceptible, though less so - thank you Dr. Webhill for having me add this). The reasons for which I advocate puppies going outside before their full series of shots is this: all too often I meet clients who have never brought their dogs outside until 4, 5, or even 6 months of age. And why? Because they didn't have their shots. This is wrong, in my opinion. The severe problem this poses is that these dogs have never met another dog! This is when serious behavioural problems arise, and this is when these pets are given up for these very problems! So you see, we need to expose these puppies to other dogs lest we end up with a dog that is severely unsocialized. We also need to understand the risks, and assume them. Again, I recommend that puppies be vaccinated at 8, 12, and 16 weeks, and that they receive a "kennel-cough" shot at 8 or 12 weeks. This should be followed by puppy classes after 10-12 weeks. I think it's reasonable to start letting these puppies outside, under close supervision, on a leash, about 1-2 weeks after the 2nd shots, if not earlier.
Any puppy that is vomiting, has diarrhea, and is lethargic, I would consult with a vet immediately for fear of parvovirus, a dangerous infectious disease that can cause fatal vomiting and diarrhea.
A sick little "parvo puppy."
