Impetigo (im-puh-TIE-go) is a very common skin infection among children. It produces blisters and sores, which usually appear on the face and hands, although they may show up anywhere on the body. The infection is contagious and often spreads from one child to another in childcare facilities or classrooms.

More Than a Little Itch: Ariana's Story

Impetigo, a bacterial skin infection, occurs as scattered thin-walled skin blisters containing clear yellow or slightly turbid fluid without surrounding redness.

Impetigo, a bacterial skin infection, occurs as scattered thin-walled skin blisters containing clear yellow or slightly turbid fluid without surrounding redness.
SPL/Science Source.

What Is Impetigo?

Impetigo is one of the more common skin infections seen in children. Impetigo produces blisters and sores, usually by the nose and face, or on the hands and forearms. It is very contagious * and can readily spread to other parts of the body, too. This infection can also spread from one person to another. Impetigo usually clears up with a simple antibiotics * treatment. If it is not treated, however, the infection can become more serious and lead to other, much more dangerous conditions.

What Causes Impetigo?

Bacteria * cause impetigo. Two common bacteria that lead to impetigo are Streptococcus pyogenes and Staphylococcus aureus. Both bacteria are too small to be seen by the naked eye. S. pyogenes are round and form chains, so they look a little like strings of pearls. Besides impetigo, this bacteria can cause other illnesses, such as strep throat * (also known as acute pharyngitis), rheumatic fever * , and scarlet fever * . S. aureus, which is round and sometimes goes by the name golden staph, can also cause other illnesses besides impetigo. Some of these illnesses, such as pneumonia * and toxic shock syndrome, can be life threatening.

In impetigo, both S. pyogenes and S. aureus can infect people when they touch something that has the bacteria on it. For instance, a boy who has impetigo on his hands may dry them on a towel. If a girl then uses the same towel, the bacteria can infect her, and she can develop impetigo herself. These bacteria often infect the skin through a cut or other sore that a person has, but they can also infect unbroken, healthy skin.

Who Gets Impetigo?

Impetigo is especially common among infants and among children up to six years of age. The infection is known as school sores, because it is especially widespread among young, school-aged children who pass it along to their classmates through direct contact. In other words, one child may purposely or inadvertently touch the wound of another child and become infected. Impetigo often spreads from child to child very quickly in childcare centers and classrooms. The more crowded the children are, the more likely impetigo will spread.

What Are the Symptoms of Impetigo?

Impetigo comes in two main types: impetigo contagiosa and bullous impetigo. A third type of skin infection, known as deep impetigo or ecthyma, also occurs. Each type has its own set of symptoms.

Impetigo contagiosa

Most people who have impetigo have the form called impetigo contagiosa (cun-tay-gee-O-suh), which is also sometimes known as nonbullous impetigo. A person with this condition first has a red sore at the site of the infection. Common places for the infection are next to the nose or mouth. The sore oozes liquid, sometimes pus, which hardens into a yellow or brown-colored crust. As the sore heals, the crust disappears, and the underlying red mark heals up without leaving behind a scar. Most children have several such sores near one another. These sores may itch, and children may scratch them. If the child then touches another area of the body without washing first, the bacteria can spread and produce sores elsewhere on the body.

Sometimes a child will also have swollen lymph nodes * near the sores.

Bullous impetigo

An infection of the S. aureus bacterium is the cause of bullous (BULL-us) impetigo. This type mainly affects babies and children up to two years of age, although older children and adults are sometimes affected. Children with bullous impetigo get red sores with large, liquid-filled blisters that may look painful, but are not. They are, however, itchy. These blisters often appear on arms and legs and on the trunk of the body. Eventually, these blisters burst and, as happens in impetigo contagiosa, a yellowish to brownish crust forms and later disappears. The underlying red mark in bullous impetigo may heal more slowly than sores from other forms of impetigo. Bullous impetigo appears to be less contagious than impetigo contagiosa.

Sometimes teachers, childcare workers, or other people may think that the sores look like cigarette burns or scald injuries and mistakenly think that the child is the victim of child abuse, but a doctor can set the record straight.

Deep impetigo

How Is Impetigo Diagnosed?

A doctor typically needs only look at the sore to diagnose it as impetigo. Occasionally, the doctor may order a test to confirm the diagnosis, but usually this is not necessary.

How Is Impetigo Treated?

Impetigo will often heal by itself within several weeks and leave no scars behind. Doctors, however, often treat it to help with the itching or with the soreness and to prevent the bacteria from spreading from one person to the next. Common treatments are antibiotic ointments such as mupirocin (myoo-PEER-o-sin, Bactroban) and retapamulin (Altabax). Typically, doctors recommend carefully washing the site and gently removing the crust and then applying the ointment. Sometimes the doctor may prescribe an antibiotic, such as a penicillin, cephalosporin, or macrolide, which is taken by mouth.

In some people, impetigo may recur. These patients usually become so familiar with the sores that they are able to notice them and treat them very early. They should, however, report the return of the condition to the doctor. The physician may be able to find out where the impetigo-causing bacteria are living—for instance, in the person's nose or elsewhere on the body—and may be able to apply antibiotics to that location to wipe out the bacteria once and for all.

If left untreated, impetigo can become a dangerous infection, one that may lead to more serious problems in the lungs, kidneys, joints, or bones.

Can Impetigo Be Prevented?

Medical professionals recommend the following to help children and others avoid getting impetigo or from spreading it to other people:

See also Bacterial Infections • Skin Conditions: Overview


Books and Articles

Pereira, Luciana Baptista. “Impetigo.” Brazilian Society of Dermatology 89, no. 2 (2014): 293–9. (accessed July 20, 2015).


MedlinePlus. “Impetigo.” U.S. National Library of Medicine. (accessed July 20, 2015).

National Eczema Association. “Impetigo.” (accessed July 20, 2015).

New York State Public High School Athletic Association. “Best Practices for Preventing Skin Infections.” (accessed July 20, 2015).


American Osteopathic College of Dermatology. 1501 E. Illinois St., PO Box 7525, Kirksville, MO 63501. Toll-free: 800-449-2623. Website: (accessed July 20, 2015).

* contagious (kon-TAY-jus) means transmittable from one person to another, usually referring to an infection.

* antibiotics (an-tie-by-AH-tiks) are drugs that kill or slow the growth of bacteria.

* bacteria (bak-TEER-ee-a) are single-celled microorganisms, which typically reproduce by cell division. Some, but not all, types of bacteria can cause disease in humans. Many types can live in the body without causing harm.

* strep throat is a contagious sore throat caused by a strain of bacteria known as Streptococcus.

* rheumatic fever (roo-MAH-tik) is a condition associated with fever, joint pain, and inflammation affecting many parts of the body, including the heart. It occurs following infection with certain types of strep bacteria.

* scarlet fever is an infection that causes a sore throat and a rash.

* pneumonia (nu-MO-nyah) is inflammation of the lungs.

* lymph nodes (LIMF) are small, bean-shaped masses of tissue containing immune system cells that fight harmful microorganisms. Lymph nodes may swell during infections.

Disclaimer:   This information is not a tool for self-diagnosis or a substitute for professional care.

(MLA 8th Edition)