It is a false belief that pet do not bite their owners. Pets may bite when frightened, injured, or when disturbed when they are eating or sleeping.  Dog bites can be very violent, and fractures and other tissue injuries can occur, especially in young children. Dog bite injuries in children often occur on the head and neck, and deaths are known. These usually result from injury to the large blood vessels in the neck. Cats, on the other hand, usually do not bite unless provoked.  Animals have many germs in their mouth that can cause disease in humans. The germs exist in the animals' saliva, and it is important to realize that a lick can also transmit the disease. Also, animals frequently lick their claws, so a scratch may be as bad as a bite.

The most dangerous infection transmitted by animal bites is rabies. This is a viral infection, and is 100% fatal. There is no cure, no treatment, and is spread through the saliva of an infected animal.  It may be prevented by vaccinating the bitten person immediately after the bite, and all pets should be vaccinated against rabies according to state regulations.  An animal which bites without provocation should be suspected for rabies.  Anyone that is bitten by an animal whose rabies status is unknown should go to the hospital for medical attention as soon as possible.  Animal control should be notified right away so that they can seize the animal in case a rabies test is necessary.

The most common infection transmitted by animal bites is Pasteurella multocida. This germ exists in the mouth of healthy animals like cats and dogs, and can cause infections at the site of a bite. Rarely, it has been known to cause serious infections like meningitis. Most commonly, animal bites will result in redness, pain, and swelling around the wound, pus and abscess formation, redness of the involved lymph vessels (lymphangitis), and fever. Apart from P. multocida, other germs involved may be Pasteurella canis, Pasteurella septica, streptococci, staphylococci, moraxella, and neisseria. Cat bites can also transmit Cat Scratch disease.