An infected finger can be caused by many different types of bacteria, and bacteria is usually the cause of an infected finger. However in the case of herpetic whitlow it is caused by a virus which is the herpes simplex virus. An infection can get into the finger via a puncture wound, cut or animal bite.
There are five different types of bacteria that can cause a finger infection. The different types of bacteria usually have unique entry points, and affect different parts of the finger. One bacteria is called paronychia. Paronychia can be a result of a strep or staph infection. What happens in this instance is that a hangnail will be on the finger, and one will attempt to remove the hangnail by biting it off.This can cause a wound that is the bacteria’s point of entry. The bacteria that is in the mouth and on the hand of the finger enter the open wound and cause infection. The bacteria can then get into the skin around the nail and the nail itself. This infection is usually minor. Next, another infection caused by the same bacteria is called felon. This bacterial infection is usually the result of a deep puncture wound, for instance if a nail punctures the finger. It usually attacks the padding of the finger, and stays in that location only.Cellulitis is yet another that starts within the finger but spreads easily throughout the rest of the hand and infects other fingers. It is caused by strep and staph bacteria just as paronychia. It can enter through an open wound in one finger and be carried throughout the hand by the blood.
Deep space infection is another type, it is called this because the puncture or other type of wound reaches into the deep tissue of the finger infecting it. An abcess due to the infection can develop on the webs between the fingers. Due to the infection being deep in the finger, it allows for easier spread of the bacteria throughout the hand. Another type of deep infection of the finger is called flexor tenosynovitis, and it is usually caused by a trauma that is penetrative. The bacteria then infects the tendons and sheath of the finger.
Lastly is herpetic whitlow. This is an infection caused by the herpes simplex virus, and it can be either type or type 2. Children and people who work in the medical and dental field are more at risk for this type. The entry point of this virus can be any wound, or break in skin on the finger or hand, and causes fluid filled blisters on the hand. The herpes virus is very contagious, and can be passed from person to person, as well as from body part to body part, for example from mouth to hand, or genitals to hand.
There are many causes to an infected finger, mostly a bacterial cause. If one thinks they have an infection they should check with their health care provider immediately.