Impetigo: All You Need to Know
Impetigo (im-peh-TIE-go) is a bacterial infection of the skin that is more common in young children than other ages. Doctors use antibiotics to treat impetigo and prevent rare, but serious long-term health problems. Antibiotics can also help protect others from getting sick.
Impetigo is a skin infection caused by one or both of the following bacteria: group A Streptococcus and Staphylococcus aureus. This page focuses on impetigo caused by group A Streptococcus, which are also called group A strep. In addition to impetigo, group A strep cause many different infections.
When group A strep infects the skin, it causes sores. The bacteria can spread to others if someone touches those sores.
In general, impetigo is a mild infection that can occur anywhere on the body. It most often affects exposed skin, such as around the nose and mouth or on the arms or legs.
Symptoms include red, itchy sores that break open and leak a clear fluid or pus for a few days. Next, a crusty yellow or “honey-colored” scab forms over the sore, which then heals without leaving a scar.
It usually takes 10 days for sores to appear after someone is exposed to group A strep.
Anyone can get impetigo, but some factors increase someone’s risk of getting this infection.
- Age: Impetigo is most common in children 2 through 5 years old.
- Climate: Impetigo is more common in areas with hot, humid summers and mild winters (subtropics), or wet and dry seasons (tropics).
- Infections or injuries that break the skin: People with scabies infection are at increased risk for impetigo. Participating in activities where cuts or scrapes are common (sports) can also increase someone’s risk of impetigo.
- Close contact or crowding: Close contact with another person with impetigo is the most common risk factor for illness. For example, if someone has impetigo, it often spreads to other people in their household. Infectious illnesses also tend to spread wherever large groups of people gather together. Crowded conditions — such as those in schools and daycare centers — can increase the spread of impetigo.
Doctors typically diagnose impetigo by looking at the sores (physical examination). Lab tests are not usually needed.
Impetigo is treated with antibiotics that are either rubbed onto the sores (topical antibiotics) or taken by mouth (oral antibiotics). A doctor might recommend a topical ointment, such as mupirocin or retapamulin, for only a few sores. Oral antibiotics can be used when there are more sores.
Complications, including kidney problems (post-streptococcal glomerulonephritis), are very rare. If someone has complications occur, they usually have them one to two weeks after the skin sores go away.
People can get impetigo more than once. Having impetigo does not protect someone from getting it again in the future. While there is no vaccine to prevent impetigo, there are things people can do to protect themselves and others.
Keep sores caused by impetigo covered in order to help prevent spreading group A strep to others. If you have scabies, treating that infection will also help prevent impetigo.
Common sense and good wound care are the best ways to prevent bacterial skin infections, including impetigo:
- Clean all minor cuts and injuries that break the skin (like blisters and scrapes) with soap and water.
- Clean and cover draining or open wounds with clean, dry bandages until they heal.
- See a doctor for puncture and other deep or serious wounds.
- If you have an open wound or active infection, avoid spending time in:
- Hot tubs
- Swimming pools
- Natural bodies of water (e.g., lakes, rivers, oceans)
You should wash the clothes, linens, and towels of anyone who has impetigo every day. These items should not be shared with anyone else. After they have been washed, these items are safe for others to use.
- Cover your mouth and nose with a tissue when you cough or sneeze
- Put your used tissue in the waste basket
- Cough or sneeze into your upper sleeve or elbow, not your hands, if you don’t have a tissue
- Wash your hands often with soap and water for at least 20 seconds
- Use an alcohol-based hand rub if soap and water are not available
Someone with impetigo is usually not able to spread the bacteria to others after the lesions heal. People diagnosed with impetigo can return to work, school, or daycare if they:
- Have started antibiotic treatment
- Keep all sores on exposed skin covered
Use the prescription exactly as the doctor says to.