Impetigo

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Overview
Impetigo is a superficial skin infection most common among children age 2–6 years. People who play close contact sports such as rugby, American football and wrestling are also susceptible, regardless of age. The name derives from the Latin impetere ("assail"). It is also known as school sores.

Transmission
The infection is spread by direct contact with lesions or with nasal carriers. The incubation period is 1–3 days. Dried streptococci in the air are not infectious to intact skin.

Diagnosis
The diagnosis is made based on the typical appearance of the skin lesion.

Common Causes
Impetigo is usually caused by Staphylococcus aureus, it may also be caused by the same streptococcus strain that causes strep throat, Streptococcus pyogenes.

According to the American Academy of Family Physicians - "Nonbullous impetigo was previously thought to be a group A streptococcal process and bullous impetigo was primarily thought to be caused by S. aureus. Studies now indicate that both forms of impetigo are primarily caused by S. aureus with Streptococcus usually being involved in the nonbullous form"

Scratching may spread the lesions.

Signs and symptoms
One or more pimple-like lesions surrounded by reddened skin. Lesions fill with pus, then break down over 4–6 days and form a thick crust. Impetigo is often associated with insect bites, cuts, and other forms of trauma to the skin. Itching is common.

People who suffer from cold sores have shown higher chances of suffering from impetigo. Those who normally suffer from cold sores should consult a doctor if normal treatment has no effect.

Treatment
Topical or oral antibiotics are usually prescribed.

Treatment may involve washing with soap and water and letting the impetigo dry in the air.

Many general practitioners choose to treat impetigo with bactericidal ointment, such as fusidic acid (Fucidin) or mupirocin (Bactroban), but in more severe cases oral antibiotics, such as flucloxacillin (e.g. Floxapen) or erythromycin (e.g. Erythrocin) or Dicloxacillin are necessary.

It is very important to remove the crusts before applying ointment, because the bacteria that cause the disease live underneath them.