Obviously, rabies, bacterial infection from a dog bite and exposure to infected urine from cases of canine leptospirosis can a danger to humans. Yet there are a few diseases that both dog and owner share.
Some fungal skin diseases such as ringworm and mite known as scabies or mange can transmitted from dogs to humans. But if the habitat is kept clean, the chances of contamination are decreased.
Several worms and protozoa parasites can affect people, but routine hygiene greatly lessens exposure.
But the following aren't transmittable to humans:
canine distemper
infectious canine hepatitis'
Parvoviral gastroenteritis
coronaviral gastroenteritis
Even more so, there isn't very many cases where a dog has contracted a disease from a human. But one of the few is where a canine contracted TB from their owner.