What is cellulitis?

Cellulitis is a bacterial infection of the skin and the tissues beneath it. The bacteria usually penetrate the skin's protective outer layer at an area of trauma or injury, such as a cut or an animal bite. Once past this outer layer, invading bacteria are often killed by the immune system. In some cases however, they can multiply causing an inflammation within the skin.

What causes cellulitis?

Cellulitis is caused by different types of bacteria. For example; if cellulitis develops due to a common household cut, the bacteria responsible is usually either Streptococcus pyogenes or Staphylococcus aureus. If cellulitis develops due to a cat bite, the culprit is usually Pasteurella multocida.

There are many other ways in which bacteria can get through the skin, such as dog bites or through surgical wounds.

Sometimes cellulitis develops even when there is no apparent skin trauma or injury. This is because the cellulitis-causing bacteria can enter through microscopic openings in the skin.

People who have poor immune systems, such as people with AIDS, are more prone to cellulitis.

What does cellulitis look like?

An area of the skin with cellulitis looks inflamed. There is usually swelling of some sort that is red in colour, feels warm, and is painful. This inflamed patch can rapidly grow within the first 24 hours.

Cellulitis may appear on a part of the skin where there has been some sort of a trauma or injury, such as an animal bite.

What are the symptoms of cellulitis?

Apart from the red, painful inflammation described above, symptoms can include fever, chills, and a general feeling of ill health.

What is orbital cellulitis?

When bacteria infect the tissues surrounding the eye, it is known as orbital cellulitis. This can lead to red, swollen eyes, and can be quite painful. This is a serious infection. If you notice any redness, swelling or pain around your eyes, visit your doctor or optician immediately.

Is cellulitis contagious?

No. Cellulitis is not contagious because it is an infection of the tissues underneath the outer layer of skin. Therefore while the infection is apparent due to a rash on the (outer) skin, this acts as a cover over the infection underneath.

How is cellulitis prevented?

How long does cellulitis last?

This depends on the type of infecting bacteria, the type of skin injury (if there is one), and the general health of the person involved.

If medically treated, most cases of cellulitis clear up within 10 days.

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