Impetigo (sometimes impetaigo) is a superficial bacterial skin infection most common among children 2 to 6 years old. 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.
It is primarily caused by Staphylococcus aureus, and sometimes by Streptococcus pyogenes. According to the American Academy of Family Physicians, both bullous and nonbullous are primarily caused by S. aureus, with Streptococcus also commonly being involved in the nonbullous form.
Impetigo generally appears as honey-colored scabs formed from dried serum, and is often found on the arms, legs, or face.
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. Scratching may spread the lesions.
Good hygiene practices can help prevent impetigo from spreading. Those who are infected should use soap and water to clean their skin and take baths or showers regularly. Non-infected members of the household should pay special attention to areas of the skin that have been injured, such as cuts, scrapes, bug bites, areas of eczema, and rashes. These areas should be kept clean and covered to prevent infection. In addition, anyone with impetigo should cover the impetigo sores with gauze and tape. All members of the household should wash their hands thoroughly with soap on a regular basis. It is also a good idea for everyone to keep their fingernails cut short to make hand washing more effective. Contact with the infected person and his or her belongings should be avoided, and the infected person should use separate towels for bathing and hand washing. If necessary, paper towels can be used in place of cloth towels for hand drying. The infected person’s bed linens, towels, and clothing should be separated from those of other family members, as well. Whilst suffering from impetigo it is best to stay indoors for a few days to stop any bacteria getting into the blisters and making the infections worse. When a person has impetigo it is common for him/her to get it a 2nd time in the space of 6 – 9 months. This usually occurs in persons aged 12 – 16.
Impetigo contagiosa has pimple-like lesions surrounded by reddened skin. Lesions fill with pus, then break down over 4–6 days and form a thick, honey-colored crust. Impetigo is often associated with insect bites, cuts, and other forms of trauma to the skin. Itching is VERY 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. Impetigo also causes flu-like symptoms which may cause fatigue, weakness of muscles, headaches and vomiting.
Bullous impetigo primarily affects infants and children younger than 2 years. It causes painless, fluid-filled blisters — usually on the trunk, arms and legs. The skin around the blister is usually red and itchy but not sore. The blisters, which break and scab over with a yellow-colored crust, may be large or small, and may last longer than sores from other types of impetigo.
Ecthyma is a more serious form of impetigo in which the infection penetrates deeper into the skin’s second layer, the dermis. Signs and symptoms include:
For generations, the disease was treated with an application of the antiseptic gentian violet. Today, topical or oral antibiotics are usually prescribed. Treatment may involve washing with soap and water and letting the impetigo dry in the air. Mild cases may be treated with bactericidal ointment, such as fusidic acid, mupirocin or neosporin, which in some countries may be available over-the-counter. More severe cases require oral antibiotics, such as dicloxacillin, flucloxacillin or erythromycin. Alternatively amoxicillin combined with clavulanate potassium or cephalosporins (1st generation) may also be used as an antibiotic treatment.