Wild Animals Can Spread Disease to Pets
The skunk was captured by San Francisco's department of Animal Care and Control. It had been behaving erratically, staggering, and acting disoriented. Animal Care and Control did not have a veterinarian on duty at the time (it was the middle of the night), so the officer brought the skunk to the emergency hospital where I was working for euthanasia (the skunk's condition was deemed to be beyond help).
The skunk's likely diagnosis was canine distemper virus--the same virus that causes serious disease in dogs, wild canids, marine mammals, and African lions.
For the most part, diseases tend to be species specific. Dogs most often catch diseases from other dogs. Cats catch diseases from other cats. Humans catch diseases from other humans.
But there are exceptions. Rabies is the most famous exception. The virus can infect any mammal. Many parasitic worms can infest multiple species. Feline toxoplasmosis can infect humans, sea otters, and wild cats. Canine distemper virus can infect a variety of wild animals.
Fortunately, basic hygiene and vaccinations can protect your pet from many wildlife-borne diseases.
Pets who have minimal exposure to other members of their species (such as indoor cats and small dogs that rarely go out) may still be at risk for exposure to wildlife. Talk to your vet about these risks, and make life style and vaccination decisions accordingly.