Impetigo is a skin infection that is characterized by red sores that develop crusty yellow scabs. They can form fluid-filled blisters that burst or seep. It mostly affects babies and preschool children, but not always. It is caused by streptococci and streptococcus bacteria, and it is highly contagious.
Those with poor hygiene are at greatest risk, but it can infect anyone, especially when the skin is broken by insect bites, illness or injury. High humidity is also a risk factor, but some naturally carry the bacteria in the nasal passages. The spread of impetigo can be prevented through good hygiene and by not sharing items that come in contact with the skin.
The initial symptom of impetigo is one or more red skin lesions. The sores appear most often around the mouth, nose and on the legs, but they can form anywhere on the skin. The sores form scab-like yellowish crusts and pustules that break and ooze. The lesions may itch or slightly hurt, but most cause little to no discomfort when left alone.
Impetigo is caused by an infection of either Staphylococcus aureus or Streptococcus pyogenes, which are types of bacteria. While these bacteria can live on the skin harmlessly, if they enter deeper layers of tissue, often through a minor wound, the infection occurs.
In most cases of impetigo, the wound which allowed the infection to occur is mild enough that you wouldn’t typically notice it. It might be a mild cut, graze or insect bite, for example, or anything else which breaks the surface of the skin. This is known as primary impetigo.
In other cases, the skin may have become damaged by another skin condition which breaks the surface. This could be something like head lice, which causes the skin to itch and can result in grazes on the scalp, or eczema which can cause skin to crack. This is known as secondary impetigo.
Often, the bacteria which causes impetigo is spread from close contact with someone else who has the infection. Sometimes direct physical contact can result in transmission of impetigo. In other cases, sharing towels, flannels or clothing with someone with impetigo can result in it spreading.
Impetigo is usually treated with topical antibiotic medication. When scabs and crusts are thick, they may be removed by soaking or covering the areas with warm moist compresses. Gently removing the crusts enables the medication can reach the infected tissue. Those with several lesions may also be prescribed antibiotics by mouth.
Impetigo can spread from an infected individual for as long as the sores remain wet and unhealed. To avoid contracting the infection during this time, avoid close physical contact with the affected individual. Those with impetigo sores should stay away from school or work until the sores have dried up and healed.
Do not share towels, clothes or sheets with someone with impetigo, and ensure these items are washed at high temperatures after use. Do not touch the impetigo sores of others, and individuals with sores themselves should also avoid touching them, as this might spread them to other parts of the body or to other people.
Wash hands regularly if you have impetigo, particularly after touching the affected skin. If the sores are in places where they may be easily accidentally touched, such as on the hands or arms, cover them with loose bandages or clothes.