A German shepherd puppy should NOT be removed from its mother and littermates before 8 weeks of age (THIS IS THE LAW IN ALL 50 STATES). If you get a puppy earlier then 8 weeks old, then you’re robbing your puppy of the most important socialization building period with the mother and siblings. Yes, the pup may be capable of leaving at 6 weeks old but if you want a well socialized puppy then it should remain with mom and littermates for another 2 weeks for a better dog social skills throughout the dog life. That’s when dog socializing goes on – during these weeks and with its littermates and other attending adult dogs, not with strange dogs from outside the pack during the next 2 months. There is no reason or need to trust other dogs at this point.
This leaves you with a total of 8 weeks that the puppy must be kept from other dogs (between 8 weeks and 16 weeks). This isn’t a very long time to “ruin” a dog in terms of dog socialization. This, as a matter of fact, is the most important time in bonding with YOU, not other dogs. The nice side effect of keeping your pup away from other dogs at this point is that it makes you spend more direct time with the dog. If you feel that you absolutely must have the pup socialize with other dogs during this period, reunite the pup with its littermates, its dam, or other members of its direct pack. If this isn’t possible, any other dogs in your own house will be sufficient. If you don’t have other dogs, then you shouldn’t go any further.
Pet fairs, dog events, contests, and doggie parks are the worst place to bring your pup before 16 weeks of age precisely because they have so many other dogs. I cringe every time I see a young one at any of these events. These are prime places for the communication of nasty diseases and increase the pup’s exposure 1000-fold. (Remember what happened when one kid in school got chicken pox?). There is almost always no vaccination requirement for these events. Infectious diseases such as kennel cough and the like run rampant at these places. Ask regular pet-event travelers how many times their dogs have “picked up” some cough or diarrhea at one of these affairs. For an adult dog, kennel cough is merely a nuisance. For a young pup, it may be life-threatening.
Just because any particular dog is vaccinated doesn’t mean it isn’t a carrier of a serious canine disease. The dog may be an asymptomatic carrier. Or, remember, disease agents can travel on, in, or with a dog, immunized or not.
An immunization prevents a dog from getting a disease – it doesn’t prevent it from carrying it. My dog may be vaccinated for parvo but still may harbor it in its feces, intestinal tract, in its paws, on its coat, wherever. Vaccinated dogs tend to go everywhere – especially where other non-vaccinated dogs roam.
Your neighbor’s dog may seem safe but when you consider that it goes down to the local park where all the non-vaccinated dogs wander, and defecate, and sneeze, etc. and then comes back to your house, your pup isn’t safe at all. Even people can bring parvo in on the bottom of their shoes or on their hands. This is why very few outside visitors should be allowed in the house when there is a litter present – you never know where they’ve been.