10 Common Questions About Impetigo

Impetigo is a contagious bacterial skin infection that mainly affects young children. (1) “Children get impetigo when they come into contact with someone who is infected or if they’ve shared some of the same clothes, bedding, towels, or other intimate articles of an infected person,” says Lisa Denike, MD, a pediatrician with Kaiser Permanente based in Vancouver, Washington.

It’s extremely common — there are more than three million cases in the United States each year. (2) In Europe, 2 out of every 100 children contract impetigo annually, making it the most common skin infection among kids. (3)

Here, we answer 10 frequently asked questions associated with impetigo and its diagnosis, symptoms, and treatments.

1. Is Hand, Foot, and Mouth Disease the Same Thing as Impetigo?

No. Though hand, foot, and mouth disease is also found in young children and is also contagious, it’s a virus, whereas impetigo is a bacterial infection. (4)

Normally, the easiest way to tell the difference between impetigo and hand, foot, and mouth disease is to note where the rash and sores appear. Hand, foot, and mouth disease, by definition, appears frequently on the palm, soles, and inside the mouth, while impetigo does not show up in the mouth. Sounds straightforward, but Vikash S. Oza, MD, a pediatric dermatologist at NYU Langone Health in New York City, says that recent strains of hand, foot, and mouth disease appear outside of the mouth instead of inside, making it appear more like impetigo.

Be on the lookout for other symptoms: Hand, foot, and mouth disease is often accompanied by fever, loss of appetite, irritability, and sore throat, while impetigo in the early stages is strictly a skin condition. (4)

2. Typically, How Is Impetigo Diagnosed?

Often, your healthcare provider will identify impetigo simply by looking at the skin. (5)

Normally, if the provider feels confident the person is displaying signs of impetigo, a lab test won’t be needed. But Dr. Denike says a doctor may take a sample from the skin to do a bacterial culture if the infection doesn’t go away after treatment. They will test the sample in the lab to determine the type of bacteria causing the issue. (5)

It usually takes about 48 hours to get results, Dr. Oza says.

3. Impetigo Is Common in Kids — but Can Adults Get the Condition, Too?

Impetigo is most common among children or teenagers who engage in high-contact sports like wrestling, says Suzanne Friedler, MD, a board-certified fellow of the American Academy of Dermatology and a clinical instructor at Mount Sinai Medical Center in New York City. But adults can get impetigo as well.

Because adults don’t engage in as much skin-to-skin contact as children do, oftentimes a child will pass impetigo to a parent. “It is contagious, typically through contact, so sometimes in more extensive cases of impetigo we’ll start to see other family members who are affected,” Oza says.

4. Based on What We Know, What Is the Main Cause of Impetigo?

Impetigo is caused by bacteria, either streptococcus (the cause of strep throat) or staphylococcus (which causes staph infections). (3) These bacteria are all around us every day but can become an issue if the bacteria enter the skin, which they do can if there’s a cut, scrape, bug bite, rash, or a skin condition like eczema.

Impetigo is more common in the summer and in warm, humid climates, but it can occur anywhere, according to the Centers for Disease Control and Prevention (CDC).

5. Do You Need Antibiotics to Heal Impetigo?

Treating impetigo with antibiotics speeds up the healing process, with improvement often in just a few days, and it keeps the infection from spreading. Impetigo may go away on its own within two to four weeks, but not treating it means it’s likely to spread to other people or other parts of the body. (2,6)

Unfortunately, there isn’t an over-the-counter treatment option available, so antibiotics are needed to zap the bacteria. For a mild case, doctors will likely prescribe a topical antibiotic that is applied directly to the skin. For more widespread cases, oral antibiotics may be necessary. (2)

6. What Are the Signs and Symptoms of Impetigo?

“Within three days of infection, a person will develop small red spots,” Denike says of nonbullous impetigo. These usually occur around a child’s nose, mouth, or limbs. (6) The spots can turn into blisters, and when they burst, honey-colored crust takes their place. (3)

Bullous impetigo, the less common type, is marked by fluid-filled blisters on the arms, legs, or area between the neck and the waist. (6) When these burst, yellow crust appears.

Nonbullous impetigo sores are not painful, but bullous blisters can be. (6)

7. Generally, How Long Will It Take for Impetigo to Go Away?

A doctor might prescribe an antibiotic for 7 to 10 days, though you will likely see a response within 72 hours, Oza says. Impetigo may go away within a few weeks on its own. (6)

8. Is Impetigo Contagious, and if So, How?

Yes, impetigo is contagious. (2) “If the child or infected person scratches or touches the sore and then touches a surface or a toy, other children can get it if they touch that same surface or toy,” Denike says. “For this reason, it spreads easily in day care and schools.”

An abrasion in the skin — such as a scrape or a bug bite — gives the bacteria an entry point, which can lead to infection. (2) The infection is no longer contagious 24 hours after starting an antibiotic treatment. If left untreated, however, it will remain contagious for several weeks. (3)

9. If You Suspect It’s Impetigo, at What Point Should You Call a Doctor?

Although impetigo can be confused with other skin conditions, going to see a doctor if you show symptoms can help ensure you get the right diagnosis. “It’s important to contact the doctor right away, because an infected child typically needs treatment, and it’s contagious,” Denike says. You should visit a doctor if you see classic signs of impetigo.

10. How Can You Help Keep Impetigo From Spreading to Others?

Existing infections that are localized should be treated with topical antibiotics and covered with a bandage, the CDC says.

Parents should also keep the child’s fingernails trimmed. This will keep bacteria from getting under the nail and spreading when the child scratches other parts of the body. Other people in the household should also avoid sharing towels and sheets if one child has impetigo, and dirty laundry should be washed at a temperature of at least 140 degrees F. (3)