The domestic dog's health is probably one of the best-studied areas in veterinary medicine, since the dog has had such a long and close relationship with humans. Dogs can be affected by many of the same diseases, ailments, and poisons as humans.
Dogs have transferable diseases that can be passed from one dog to another, but are not transferable to humans.
However there are some exceptions to this and we'll discuss some of them here:
One that most of us are familiar with is Rabies, or Hydrophobia - This is an almost invariably fatal disease which can be transmitted to dogs or humans by the bite of an infected mammal, possibly a dog, cat, raccoon, or even a bat.
Although rodents and similar small mammals can be infected with the disease artificially, they are generally not found infected in the wild; the current hypothesis is that they are not likely to survive any attack that would infect them.
Animals with rabies suffer deterioration of the brain and tend to behave bizarrely and often aggressively, increasing the chances that they will bite another animal or a person and transmit the disease.
Areas that are rabies-free, (usually islands) such as Britain, Ireland, Australia, and the American state of Hawaii have strict quarantine laws to keep their territories rabies-free. These require long periods of isolation and observation of imported animals, which makes them unattractive places to move with a pet unless the pet is quite young. Areas that are not rabies-free usually require that dogs (and often cats) be vaccinated against rabies. While these rules may seem strict, it's necessary to protect your dog's health.
If a person or dog is bitten by an unknown dog (or other animal) you should always be treated immediately, and not wait for symptoms due to the potentially fatal consequences of a rabid bite.
To this date there has been only one case of someone surviving rabies when treatment was not begun until after symptoms appeared. The biter should be apprehended if possible, as only autopsy of the brain can determine if it was rabid.
This should be a great incentive to dog-owners to vaccinate their dogs even if they feel the risk of their dog contracting rabies is low, since vaccination will eliminate the need for their dog to be euthanized and examined in this fashion should it bite anyone or be suspected of biting anyone. This applies to dogs that are showing neurological signs at the time of the bite. Unvaccinated healthy dogs need to be confined for ten days from the time of the bite. This will need to be done at home or at a veterinarian depending on state law. If the dog is not showing signs of rabies at the end of ten days, then the person who got bit could not have been exposed to rabies.
Dogs and cats do not have the rabies virus in their saliva until a few days prior to showing symptoms. Ten day confinement does not apply to other species. A dog or cat bitten by a wild animal in an area known to have rabies should be confined for six months, because it can take that long for symptoms to start.
Other types of diseases that may affect your dog's health is spread by parasites, particularly intestinal worms such as hookworms, tapeworms and roundworms, which can be transmitted in a dog's feces. Some tapeworms have fleas as intermediate hosts: the worm egg must be consumed by a flea to hatch, then the infected flea must be ingested (usually by the dog while grooming itself, but occasionally by a human through various means) for the adult worm to establish itself in the intestines. The worm's eggs then pass through the intestines and adhere to the nether regions of the dog, and the cycle begins again.
Fleas and ticks of various species can be acquired and brought home by a dog, where they can multiply and attack humans (and vice versa). This is particularly important, now that tick-borne Lyme Disease has become endemic throughout a large area, in addition to other similar diseases such as Rocky Mountain Spotted Fever.
Although dogs do not seem to be as susceptible to such diseases as humans, similar rickettsial diseases have been spread by dogs to humans through such mechanisms as a dog killing an infected rabbit, then shaking itself off in the house near enough to its owners to fatally infect most of the family.
Leptospirosis is a bacterial disease that affects humans and animals. It is caused by bacteria of the genus Leptospira. Humans and dogs become infected through contact with water, food, or soil containing urine from infected animals. This may happen by swallowing contaminated food or water or through skin contact, especially with mucosal surfaces, such as the eyes or nose, or with broken skin. It's important to your dog's health to make sure he has fresh water to drink, so they are not likely to look for other water sources that may be contaminated.
From Wikipedia, the free encyclopedia
"A traveler must have the back of an ass to bear all,
a tongue like the tail of a dog to flatter all, the mouth of
a hog to eat what is set before him,
the ear of a merchant to hear all and say nothing." ~ Thomas Nashe