Animal Bite

An animal bite to the hand is very common and can cause pain and other problems, especially when it becomes infected. Early and proper treatment is the key to prevent problems from an animal bite.
Figure 1
Finger infection from cat bite
Figure 2
Wound infection of a thumb tip after a human bite


Animal Bite

Millions of animal bites occur in the United States each year. One of the most common is a dog bite. Other biting animals include cats, rodents, rabbits, ferrets, farm animals, monkeys and reptiles.

The major concern of an animal bite is infection. When an animal bites, bacteria from its mouth can enter the wound and begin growing. An infection can cause pain, tissue damage, or even life-threatening problems. The seriousness of a bite depends on the location, type of animal and whether a foreign object is stuck in the wound.

Infections can occur more frequently in a cat bite because cats have sharp, pointed teeth that cause deep wounds. The skin usually closes quickly over the bite, trapping bacteria (see Figure 1). However, quick and proper treatment often can prevent or minimize the risk of infection.

Rabies is a rare but a potentially fatal infection that may result from an animal bite. In the United States, wild animals such as bats, skunks, raccoons and foxes are most likely to spread rabies. Bites from these animals should be reported to your public health department.

Human Bites

Human bite wounds contain a lot of bacteria and carry a high risk of infection. Many times, these bites are the result of a fist fight. These infections can progress quickly and result in serious problems, so early treatment is necessary (see Figure 2).

Signs and Symptoms

Signs that your bite may be infected include:

  • Swelling
  • Redness
  • Warmth
  • Continued pain beyond 24 hours
  • Drainage from the wound

Signs that your infection may be spreading include:

  • Red streaks up the arm or forearm
  • Swollen glands around the elbow or in the armpit
  • Fever
  • Tiredness
  • Night sweats
  • Shakes

If these develop, you should seek emergency treatment in your physician’s office or the emergency room.

You should also seek emergency treatment if you think that the bite may have caused damage to other important structures such as the bone or nerves. Some signs that this may have happened include:

  • Bleeding that is difficult to control
  • Pale or numb finger(s)
  • Swelling or bruising
  • Deformity
  • Loss of finger motion


Getting treatment quickly can minimize the risk of problems. Your doctor will examine the wound and ask about how the injury occurred. A complete and honest account of the events will help your doctor treat you properly. For an animal bite, it is helpful if you are able to describe the type of animal, its general health, behavior, and any known rabies vaccine status. X-rays may be used to identify any damage to the hand and to look for tooth fragments.

All bites to the hand - including a dog bite, human bite, cat bite, etc. - require careful cleansing. Your doctor or other medical personnel will wash the wound and might trim away damaged skin, blood clots, or other debris that could be a source of infection. If a wound is infected, a culture swab may be obtained. This sometimes helps identify the type of bacteria causing the infection to determine which antibiotic would be most effective for treatment.

Some bites require the use of antibiotics through an IV, while others may be treated with oral medication. Sometimes people need to stay in the hospital for treatment. Serious bites usually require surgery.

Follow-up care is crucial in the case of animal bites to ensure that infection is controlled or has not developed and to restore function to the hand.

© 2016 American Society for Surgery of the Hand

This content is written, edited and updated by hand surgeon members of the American Society for Surgery of the Hand.Find a hand surgeon near you.

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