Impetigo is a common skin infection in children, but adults can get it too. It is a bacterial skin infection that usually causes red sores, blisters, or honey-colored crusts on the face, hands, and other parts of the body. This condition spreads easily through close contact, making schools and daycare centers common spots for outbreaks.
Knowing how impetigo starts, what it looks like, and how to treat it quickly can help families stop it from spreading. Early diagnosis and proper care help keep skin healthy. Learn what signs to watch for and how to protect your household at Impetigo: diagnosis and treatment.
Key Takeaways
- Impetigo is a bacterial skin infection that spreads easily.
- Fast diagnosis and treatment are important for recovery.
- Good hygiene can help lower the risk of impetigo.
What Is Impetigo?
Impetigo is a contagious bacterial skin infection that mostly affects children. It appears as red sores or blisters, often on the face, hands, and around the mouth and nose. The infection can spread quickly, especially in crowded places and warm climates.
Definition
Impetigo is a skin infection caused by bacteria, most often Staphylococcus aureus or Streptococcus pyogenes. These germs enter the skin through small cuts or insect bites.
Main symptoms are red sores, blisters, and yellowish crusts. The infection spreads through close contact or sharing personal items like towels.
Treatment with antibiotics, either as creams or pills, can clear the infection quickly. Regular handwashing helps prevent the spread.
Types of Impetigo
There are two main types: nonbullous impetigo (also called impetigo contagiosa) and bullous impetigo. Nonbullous impetigo is the most common. It starts as small red spots that turn into honey-colored crusts, often around the nose and mouth.
Bullous impetigo is less common. It causes larger blisters filled with clear or yellow fluid. These blisters break easily, leaving raw skin. Bullous impetigo mainly affects infants and young children.
Both types can cause discomfort, itching, and mild pain. Scratching may spread the infection.
Epidemiology
Impetigo is a global health problem, especially among children ages two to five. It is more common in warm, humid climates.
Crowded living conditions and limited healthcare can make outbreaks worse. Over 162 million children worldwide may have impetigo, especially in tropical regions.
Anyone can get impetigo, but it’s more likely in children and people with weakened immune systems. It is also more frequent in places where skin injuries and insect bites are common.
Causes and Risk Factors
Impetigo happens when certain bacteria invade the skin, usually through a break or damaged area. Spread often occurs among children or in crowded settings, and some factors increase the risk of infection.
Common Bacterial Causes
Impetigo is most often caused by two types of bacteria: Staphylococcus aureus and Streptococcus pyogenes (group A streptococcus). Both can live on the skin without causing problems until there is an entry point like a cut or scrape.
Staphylococcus aureus is now the leading cause, including methicillin-resistant S. aureus (MRSA), which is harder to treat. Streptococcus pyogenes is also common. Nonbullous impetigo is caused by both bacteria, while bullous impetigo is usually linked to S. aureus. More details can be found in this impetigo overview.
Transmission
Impetigo spreads easily through direct contact with sores, fluid from blisters, or items that have touched infected skin, such as towels or bedding. Children are most at risk due to frequent touching and close contact.
Bacteria enter the skin through small injuries like insect bites, scrapes, or skin conditions such as eczema or psoriasis. Overcrowded living conditions, childcare centers, and sports with skin-to-skin contact also increase transmission. Regular handwashing can help lower the risk, as noted in this diagnosis and treatment guide.
Primary Risk Factors
Several factors increase the risk of impetigo. Young children, especially ages 2 to 5, are most often affected. Broken skin from cuts or insect bites gives bacteria an easy way to enter.
Other risk factors include:
- Skin conditions: eczema, dermatitis, or psoriasis
- Chronic diseases: diabetes, HIV, or AIDS
- Exposure to scabies
- Poor hygiene or limited access to clean water
- Close contact in schools, daycares, or crowded homes
People with weakened immune systems are more vulnerable. Impetigo is especially common in warm, humid climates. More details are in this national survey from Fiji.
Symptoms of Impetigo
Impetigo is a skin infection that causes visible sores and blisters. Symptoms vary by type, but common signs include small blisters or fluid-filled spots with a yellow crust.
Early Signs
The first symptoms are small red spots on the skin. These areas may itch or feel sore. They often appear around the nose, mouth, arms, or legs, but can occur anywhere.
Early lesions quickly develop into tiny blisters filled with clear fluid. These may burst and leak, leaving wet skin.
Sometimes, mild swelling or redness can be seen around the infection. Fever is rare, but nearby lymph nodes can become swollen.
Progression of Symptoms
As impetigo gets worse, blisters may grow and multiply. The fluid in these blisters turns cloudy as pus forms. After the blisters break, a thick, sticky, yellowish-brown crust forms.
The crusts are often described as honey-colored and can cover a large area if untreated. The sores may spread to new areas if touched or scratched.
Itching is common, and scratching can cause more sores. Larger patches may develop if several blisters join together. Kids may complain of mild pain in the affected areas.
Characteristic Lesions
Impetigo causes several types of skin lesions. The most common are small blisters, vesicles, and pustules. These often burst quickly, causing wet or oozy areas.
A key feature is the honey-colored crust, especially in nonbullous impetigo. The crusts look sticky and yellow-brown, like dried honey. The area under the crust may look raw or red.
Blisters that stay intact are more common in bullous impetigo. These are larger, filled with clear or yellow fluid, and may be seen on the trunk, arms, or legs. After breaking, these usually do not crust as much but leave a sore area.
Occasionally, the sores become painful with mild swelling. The combination of blisters, crusts, and inflamed skin is a strong clue that impetigo is present. More on impetigo lesions.
Symptoms by Type
There are two main forms: nonbullous impetigo and bullous impetigo. Nonbullous impetigo is more common. It starts with small vesicles or pustules that break and form the typical honey-colored crust, usually clustering around the face and mouth.
Bullous impetigo is less frequent and usually affects infants or young children. It causes larger blisters filled with clear or yellow fluid, often on the trunk or diaper area. After the blisters burst, the area can look shiny or scaled but usually does not have much crust.
Nonbullous impetigo is usually not linked to fever or full-body symptoms. Bullous impetigo can sometimes cause mild fever or swollen lymph nodes. Severe blisters in bullous impetigo can lead to fluid loss, especially in infants, and may need hospital care. See more about impetigo types and symptoms.
Diagnosis of Impetigo
Diagnosis of impetigo relies mainly on how the rash looks and where it appears. Lab tests may help if the infection is not clear or if treatment is not working.
Clinical Evaluation
Doctors usually diagnose impetigo by looking at the skin. They check for classic signs such as honey-colored crusts, red sores, or blisters.
Healthcare providers also ask about symptoms like itching, pain, and how fast the sores appeared. They might check if the rash is spreading or if anyone else at home has a similar rash.
Other skin conditions can look like impetigo. A careful exam helps tell the difference between impetigo and eczema, herpes, or allergic reactions. A clinical exam is usually enough unless the rash is unusual or does not improve with treatment.
Laboratory Tests
Lab tests are not always needed for routine cases. If the sores look unusual or are not healing, a doctor might take a sample (swab) from the blister or crust. The sample is sent to a lab for a bacterial culture to find out the exact germ.
A culture helps if the doctor suspects another infection or needs to check antibiotic resistance. Blood tests are rarely needed. More information can be found on diagnosis and treatment of impetigo.
Treatment of Impetigo
Impetigo is usually treated with local or oral antibiotics, depending on how severe it is and how many lesions are present. Most mild cases need topical antibiotic ointment. More serious or widespread cases may require oral antibiotics.
Topical Antibiotics
For mild impetigo with limited skin involvement, topical antibiotics are usually the first choice. Ointments like mupirocin and retapamulin are preferred because they work well and have few side effects. In some areas, fusidic acid or ozenoxacin is also used, but resistance can be higher in certain regions.
Apply topical antibiotics directly to the affected skin 2-3 times a day for about 5 days. Clean the area gently with soap and water before applying the ointment. Topical treatment is usually as effective as oral antibiotics for small, localized infections. For more on topical and systemic treatments, visit this resource.
Oral Antibiotics
When impetigo affects many areas or penetrates deeper into the skin, oral antibiotics are recommended. Common options include dicloxacillin, cephalexin, erythromycin, and sometimes clindamycin.
Clindamycin or doxycycline may be used if methicillin-resistant Staphylococcus aureus (MRSA) is suspected. Doctors usually prescribe a 7-day course. Oral antibiotics are also helpful if topical agents do not work or if there is concern about infection spreading. More details can be found in this article.
When to Use Systemic Therapy
Systemic therapy (oral or intravenous antibiotics) is needed when impetigo is extensive, keeps coming back, or if there are symptoms like fever or swollen lymph nodes. It is also used if there is a risk for MRSA or deeper tissue infections.
Doctors may choose systemic antibiotics like clindamycin or doxycycline when MRSA is suspected or if usual treatments have failed. Systemic therapy is also used if the patient cannot use topical ointments or if the infection is in hard-to-reach areas. Finish the full course as prescribed to lower the chance of resistance. More information about systemic treatment options is discussed in this overview.
Home Care and Supportive Measures
Good home care helps manage impetigo symptoms, promotes healing, and prevents the infection from spreading. Keeping the skin clean and handling discomfort are important for all ages.
Wound Care
The main goal is to keep the skin clean and stop the infection from spreading. Wash the infected area gently with warm water and mild soap at least once a day. Use disposable paper towels or a clean cloth for drying and throw away or wash them after use.
Anyone who touches the sores should wash hands well with soap and water. Keep fingernails short and avoid scratching the sores. Cover infected areas with loose gauze or small bandages to protect the sores and reduce the risk of spreading bacteria. Change bandages if they get wet or dirty. Good personal hygiene, such as washing hands before and after care, lowers the chance of spreading impetigo to others or other body parts.
Managing Discomfort
Impetigo can cause itchiness, soreness, or mild pain. Use cool compresses on the sores for a few minutes to help with itching. Over-the-counter pain relief such as acetaminophen or ibuprofen may help if soreness is bothersome.
Cutting fingernails short helps stop skin damage from scratching. Wearing cotton gloves at night can help young children avoid scratching while asleep. Loose-fitting clothing keeps fabric from rubbing against irritated skin. Regular bathing with mild soap helps wash away bacteria and lessen discomfort. Good hygiene helps control both irritation and the spread of germs.
Alternative Therapies
Some people use alternative therapies like tea tree oil or honey for skin healing, but their safety and effectiveness are not always well proven. Tea tree oil has natural antibacterial properties, but it can sometimes cause allergic reactions or skin irritation.
Dilute tea tree oil before putting it on the skin, and do not use it on broken skin or open sores without checking with a healthcare professional. Do not replace medical treatment for impetigo with alternative therapies. Always clean the skin and follow good hygiene. If considering alternative options, check the evidence and talk to a doctor before trying new products. For more information, see alternative treatments for impetigo.
Complications of Impetigo
Impetigo may look mild at first, but it can sometimes lead to more serious skin problems or affect other parts of the body. Prompt treatment lowers the risk of these issues.
Local Skin Complications
The most common local complication is deeper infection of the skin or tissues underneath. If bacteria enter through broken skin, a person may develop cellulitis, which is a painful swelling and redness spreading beyond the original sores. Sometimes lymphangitis, or inflammation of the lymph vessels, can also happen. In rare cases, impetigo can progress to ecthyma, a deeper ulcerative infection with thick, hard sores and crust. Another rare but serious problem is staphylococcal scalded skin syndrome, where toxins from the bacteria cause the skin to peel in large sheets, especially in young children.
Impetigo itself does not cause rheumatic fever, but it can lead to discomfort, scarring, or skin discoloration if not treated early. Keep the affected area clean, avoid scratching, and seek medical care if the infection gets worse or spreads.
Key complications:
- Cellulitis
- Lymphangitis
- Ecthyma
- Staphylococcal scalded skin syndrome
Secondary Infections
A serious secondary complication is post-streptococcal glomerulonephritis (also called acute poststreptococcal glomerulonephritis), a kidney problem that can occur after certain types of streptococcal impetigo. Symptoms may include blood in the urine, swelling in the face or feet, and high blood pressure. This complication is uncommon but needs medical attention and close monitoring.
Impetigo can also increase the risk for other bacterial infections in the blood or body, such as septicemia, osteomyelitis, or pneumonia if not addressed early. For more details, see these resources: Impetigo complications overview and diagnosis and treatment of impetigo.
Possible secondary infections:
- Post-streptococcal glomerulonephritis
- Osteomyelitis
- Septicemia
- Pneumonia
Prevention Strategies
Prevention for impetigo focuses on personal hygiene and stopping the spread of bacteria. Keeping skin clean and covering any cuts or sores helps stop infection before it starts.
Personal Hygiene Practices
Handwashing is one of the most effective ways to prevent impetigo. Wash hands often with soap and water, especially after touching your face or wounds. Clean hands reduce the chance of moving bacteria.
Shower or bathe regularly, especially for children who play outside or in groups. Use personal towels and washcloths instead of sharing. Clean any skin injuries right away and keep them covered with a clean, dry bandage. Keep fingernails trimmed and clean. In communities with more impetigo, better hygiene habits are especially important for prevention.
Avoiding Transmission
To avoid spreading impetigo, do not touch infected skin. People who are diagnosed should stay away from school, daycare, or work until recommended by a doctor, usually after starting treatment for at least 24 hours.
Do not share personal items like clothing, towels, razors, or bedsheets. Wash clothing, sheets, and towels that have touched sores in hot water. Clean surfaces and toys often in group settings.
Children are more likely to get impetigo in crowded places, such as schools or sports teams. Caregivers and staff should watch for signs of infection and separate anyone with sores until the area is healed or treated. Using these infection prevention measures helps limit how fast the bacteria can spread.
Impetigo in Special Populations
Impetigo affects people differently depending on age, immune health, and existing skin problems. These differences can change symptoms, risks for complications, and treatment choices.
Children
Children are the group most likely to get impetigo. The infection often happens after cuts, scrapes, or insect bites. In schools and daycare, close contact and shared items make it easier for the bacteria to spread.
Nonbullous impetigo is the most common type in kids and usually appears around the nose and mouth as red sores that turn into yellow or honey-colored crusts. Because children often touch their faces or scratch, the infection can spread to other parts of their body or to other people.
Doctors usually use topical antibiotics for mild cases. In more severe cases or where many areas are affected, oral antibiotics may be needed. Hand washing and keeping fingernails short can help lower the risk of spreading impetigo among children, especially in schools and group settings. More about how impetigo impacts children can be read in this overview.
Immunocompromised Individuals
People with weakened immune systems—such as those with HIV, AIDS, those on chemotherapy, or people taking long-term steroids—face a higher risk from impetigo. Their bodies may be less able to fight off bacteria, making the infection more severe and harder to treat.
Impetigo in these individuals can spread faster and may lead to complications like cellulitis or deeper skin infections. It is important to start treatment early. Topical antibiotics might not be enough, so oral or intravenous antibiotics could be needed.
Extra care should be taken to watch for signs of spreading infection or unusual symptoms in those with low immunity. Preventive steps, such as good skin hygiene, are also important for this group.
People With Chronic Skin Conditions
People with chronic skin conditions such as eczema, psoriasis, or diabetes have a higher risk of impetigo. Breaks in the skin from scratching or inflamed patches give bacteria an easy way in. For those with diabetes, slower wound healing can also raise the chance of infection and make it harder to clear.
Impetigo may appear on areas already affected by chronic skin problems, which can make it harder to diagnose and treat. Topical steroids, sometimes used for eczema or psoriasis, may further weaken the skin's barriers.
Treatment for impetigo in this group requires careful attention. Both the underlying chronic condition and the skin infection should be managed at the same time. It is important to keep the skin clean and avoid scratching to limit spread and prevent new outbreaks. For more on treatment considerations, see this review.
Prognosis and Long-Term Outlook
Impetigo usually improves quickly with treatment. Most children and adults recover fully within a week to ten days after starting antibiotics.
Serious complications are rare. If impetigo is not treated, it can sometimes cause deeper skin infections or, in rare cases, kidney problems called post-streptococcal glomerulonephritis.
Common Outcomes:
| Outcome | Frequency |
|---|---|
| Full Recovery | Very Common |
| Skin Scarring | Rare |
| Complications | Very Rare |
Long-term effects are almost never seen in healthy people. Scarring is unlikely because impetigo affects only the top layers of skin.
Impetigo can sometimes return, especially in children or in crowded living conditions. Good hygiene and prompt treatment help reduce the chance of repeat infections.
Doctors may suggest keeping fingernails short and cleaning wounds to prevent spread. Family members may be checked if infections keep coming back.
There is no strong evidence that impetigo leads to serious long-term health problems in most people. For more details, see this review of the long-term outlook for impetigo.
Related Skin Conditions
Impetigo can look like other skin conditions, so diagnosis is important. Many infections and irritants can cause rashes, blisters, or crusting similar to impetigo.
Differential Diagnosis
Doctors check for several diseases before diagnosing impetigo. Skin conditions that look similar include contact dermatitis, atopic eczema, and herpes simplex. Each has unique symptoms, even if some sores look alike.
Contact dermatitis often results from touching things like soaps or poison ivy. It causes itching, redness, and swelling. Herpes simplex can cause small painful blisters, usually grouped together. Eczema (atopic dermatitis) brings dry and itchy patches, especially in children.
Doctors may also consider scabies, which causes intense itching and small bumps, often at night. In some cases, staphylococcal scalded skin syndrome (SSSS) is checked for, especially if there is widespread redness and peeling. A careful exam is important for an accurate diagnosis. Learn more about distinguishing features in this review on impetigo differentials.
Conditions That Mimic Impetigo
Some skin problems are mistaken for impetigo because they also cause red, blistering, or scaly patches. Dermatitis from things like poison ivy can cause blisters and a crusty rash. Unlike impetigo, it often follows contact with the plant or another known trigger.
Scabies is caused by tiny mites that burrow into skin. It leads to intense itching and sometimes crusted areas, usually in the folds of the skin. Eczema can flare up with redness, swelling, and broken skin, which can be confused with bacterial infections.
Correct identification is important because treatments are different. Impetigo needs antibiotics, but dermatitis may improve with avoiding triggers, and scabies requires medicine to kill mites. For more comparisons, see this overview of impetigo and similar skin conditions.
Frequently Asked Questions
Impetigo is a skin infection caused by bacteria and can affect people of any age. Knowing about its symptoms, how it spreads, and treatment options helps with early care and infection control.
What are the most effective treatments for impetigo?
Doctors often recommend topical antibiotics, such as mupirocin, for mild to moderate cases. If the infection is widespread or not improving, oral antibiotics might be prescribed. Other treatments like antiseptics have been studied and can sometimes be used instead of antibiotics, especially to reduce resistance, according to a recent trial.
What are the common symptoms associated with impetigo?
Impetigo usually starts as red sores or blisters, often on the face, arms, or legs. These sores may burst and leave behind honey-colored crusts. Mild itching or soreness is also common, but pain is usually not severe.
What causes the development of impetigo in individuals?
Impetigo develops when bacteria, mainly Staphylococcus aureus or Streptococcus pyogenes, enter through a break in the skin. Scratches, insect bites, or other skin problems like eczema can make it easier for bacteria to infect the skin. It often spreads in warm, humid environments.
Is impetigo considered contagious, and if so, how does it spread?
Impetigo is highly contagious and can spread easily through direct skin-to-skin contact, such as touching the sores. It can also spread by sharing towels, clothing, or other personal items that have touched the infected skin. This makes outbreak control important, especially in group settings.
Can adults contract impetigo, and are the symptoms different from those in children?
Impetigo can affect both adults and children, though it happens more often in young children. The symptoms are usually the same, with red sores and yellowish crusts. Adults may get impetigo if they have ongoing skin problems or compromised immune systems.
What distinguishes bullous impetigo from other forms of the condition?
Bullous impetigo causes large, fluid-filled blisters that break easily and leave a yellow crust. This type is more common in newborns and young children. Nonbullous impetigo, which is more common overall, causes smaller sores with a thicker crust. Both forms are caused by bacteria but look different. Learn more about types of impetigo from an AFFP review.