Dog poop despite being so prevalent in the backyards of any dog owner is full of dangerous bacteria that can spread to other dogs. Campylobacteriosis, Salmonella and E. Coli are among bacterial culprits found in dog poop. Parasites like tapeworms, roundworms and hookworms can also live in your dog’s feces. Most dangerously and infamous is Parvovirus, causing horrible pain for puppies and can kill them.