The symptoms of animal bites vary depending on the type of animal involved.
Dog bites usually cause a deep, narrow hole in the skin (puncture wound). They can also cause a jagged wound or cut (laceration) and scrapes to the skin (abrasions).
This is because dogs use their front teeth to "pin" their victim, and their other teeth to bite and pull at the surrounding skin.
In adults, most animal bites are to the hands, arms, legs or feet. As children are smaller, most bites are to the face – usually their lips, nose or cheek.
A cat's jaws aren't as strong as a dog's, but their teeth are sharper and often cause very deep puncture wounds. A cat bite is capable of penetrating bones and joints.
Lacerations and abrasions are less common than in dog bites, but claw wounds can pass on infections because cats lick their paws.
In adults, most cat bites are to the upper limbs, particularly the fingers and hands. In children, the face and neck can also be bitten, as upper limbs.
Even small bites or scratches can lead to infections. Very occasionally, an unusual infection called "cat scratch disease" can develop, caused by a bacterium known as Bartonella henselae.
Most human bites are the result of a closed-fist injury, where one person punches another person in the teeth and cuts their hand. Typical symptoms include small cuts to the hand and red, swollen and painful skin.
Bites that occur to the finger when someone is punched in the mouth, known as occlusional bites, can sometimes lead to bacteria being implanted deep into the tissues. This can result in bone infection.
Very occasionally, viruses can be transmitted by human bites. The chances of infection occurring are about 10 times lower than after a needle stick injury or direct transmission via blood contamination. However, all human bites should be taken seriously and be assessed by a healthcare professional.
You will need to have blood tests, and you may be offered a hepatitis B vaccination and other tests, depending on the actual circumstances of the bite injury.
Signs and symptoms of infection
Signs and symptoms that suggest a bite wound has become infected include:
- redness and swelling around the wound
- the wound becoming more painful
- liquid or pus leaking from the wound
- swollen lymph glands (nodes)
- a high temperature (fever) of 38°C (100.4°F) or above
When to seek medical advice
If you or your child is bitten by an animal, seek immediate medical attention (unless the bite is very minor).
Animals have bacteria in their mouth, which can cause infection if you're bitten. Even small cat bites can sometimes penetrate deeply and become infected.
Human bites have a very high risk of becoming infected, so you should always seek immediate medical attention rather than waiting for any symptoms of infection to appear.
If you have a lowered immune system, it's also very important that you seek immediate medical attention if you're bitten by an animal or human.
Lowered immunity (immunosuppression) may be caused by a pre-existing health condition that increases your risk of infection, such as diabetes, liver disease or HIV. It can also occur after having certain types of treatment, such as chemotherapy or a splenectomy (removal of the spleen).
Minor bites can be treated by your GP or at a minor injuries unit. For more severe bite wounds involving bones, joints or tendons, visit your local accident and emergency (A&E) department.
Last updated: 26 June 2014
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