Perhaps they should do some research about puppy care. One wonders what sort of breeder they obtained the puppy from if they were not given advice on it's care!
Its not so much what it can pick up as the damage it can do to its limbs if over exercised. Unless its an extremely well used part of the forest the chances of getting a 'dog' disease are slim, but possibly could pick up ticks if there are deer. If these are not dealt with they can cause anaemia and ultimately death particularly in a very young puppy.
Probably got it from one of their mates who had bred their bitch with another mates dog and sold the puppies to anyone who had the dosh.
Daren't even ask if parents had been DNA tested for L2-HGA or HC!
Another worry is canine parvovirus. This can easily kill a puppy.The problem is that adult dogs can carry the virus and a pup can pick up the virus from the faeces of the carriers.
Awww...we've got 3 Staffies ummmm, and that little one's far too young to be out. I'd still have it with its mother at that age. Hopefully it won't pick anything serious up, or be affected in other ways, but it needs the vet to have a look at it and to advise on all injections.