Health Tips

Impetigo is a common skin infection that mainly affects infants and children. It can be caused by two types of bacteria: group A Streptococcus (Streptococcus pyogene) and Staphylococcus aureus. Impetigo is highly contagious, i.e. it can be easily spread from one person to another.

What does impetigo look like?

There are three ways impetigo may present itself:

• Non-bullous impetigo: It is the most common form of impetigo. The lesion begins as papules that progress to water-filled blisters surrounded by redness. Subsequently they become pustules that enlarge and rapidly break down to form thick, sticky crusts which are yellow brown or honey-coloured; this progress usually occurs over approximately one week. Such lesions may involve face, fingers and toes. They tend to remain at a specific location on the skin. To cause non-bullous impetigo, the bacteria would invade a pre-existing wound. 

Image credit to: Stedman's Medical Dictionary. Copyright © 2008 Lippincott Williams & Wilkins. From UpToDate

• Bullous impetigo: Bullous impetigo is a form of impetigo seen primarily in young children in which the water-filled blisters enlarge to form flaccid sacs with clear yellow fluid, which later becomes darker and more turbid. The sacs eventually ruptured and left a thin brown crust. Bullous impetigo is caused by Staphylococcus aureus that produces a specific toxin called exfoliative toxin A. 

Image credit: www.visualdx.com. Copyright VisualDx. All rights reserved. From UpToDate

• Ecthyma: When the lesions of impetigo extend deep into the inner skin layer, it becomes an ulcer called ecthyma. Such ulcers are often covered with yellow crusts.

Image credit: www.visualdx.com. Copyright VisualDx. All rights reserved. From UpToDate.

How is impetigo spread from one to another?

Impetigo easily spreads from one person to another by the following methods :

• Body contact with a person who has impetigo, especially if someone touches those sores.

• Sharing of clothes, towels or bedding with a person who has impetigo It can also spread from one part of the body to another.

Someone with impetigo is usually not able to spread the bacteria to others after the lesions heal. However, before those lesions healed, it is better to abstain from crowded places such as school, daycare centres and workplace.

Who is at risk for impetigo?

Anyone can get impetigo, but there following factors increase someone’s risk of getting it:

• Young children aged between 2 to 5 years old

• Have an infection or injuries that break the skin, such as scabies, cuts or scrapes

• Close contact with someone who contracted impetigo

• Crowded areas such as those in schools and daycare centers can increase the spread of impetigo.

• Impetigo is more common in areas with hot, humid summers and mild winters (subtropics), or wet and dry seasons (tropics).

Keep impetigo at bay!

While there’s no vaccine for impetigo, there are things you can do to protect yourself and your children from impetigo.

1. Take care of your wound (if any)

As mentioned, bacteria that cause impetigo mainly gain entry to our skin through pre-existing wounds. As such, good wound care is crucial to prevent any skin infections, including impetigo. A good wound care involves:

• Clean all minor cuts and injuries that break the skin with soap and water. Opt for mild soap to reduce irritation, or otherwise use a wound care solution to clean it.

• 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)

• Avoid scratching the wound, or at least keep nails short and clean to minimise the harm done on the wound. 

2. Practise good hygiene

The clothes, linens and towels of anyone who has impetigo should not be shared with anyone else and should be washed every day. Nonetheless, the best way to stop spreading impetigo to anyone else is to wash hands regularly. Also, practising cough and sneezing etiquette is also important.

3. See a doctor for antibiotics treatment

Since impetigo is caused by bacteria, someone with impetigo should see a doctor for appropriate treatment. After the diagnosis of impetigo is made, doctors would usually prescribe either antibiotics cream/ointment to be applied on the skin, or antibiotics pill to be taken orally by those who experience more severe symptoms. Examples of common antibiotic creams prescribed for impetigo are mupirocin and fusidic acid. 

It is important to note that you should not self-diagnose and treat yourself for any skin conditions. If you happen to have a skin condition similar to what is described for impetigo, you are still encouraged to see a healthcare professional for diagnosis, as there can be other types of skin conditions that might be mistaken for impetigo.

What if impetigo is not treated properly?

The severe complications of an untreated impetigo include:

• Soft tissue infection, such as cellulitis and lymphangitis. They may further progress into even more severe infections including osteomyelitis, septic arthritis or pneumonia.

• Staphylococcal scalded skin syndrome (SSSS)

• Poststreptococcal glomerulonephritis 

• Rheumatic fever

While these scientific phrases may sound mouthful, just know that an untreated impetigo can lead to severe infections which are complicated to treat. These complications often may result in hospitalisation or even death.

Resources:

1. Mayo Clinic - Impetigo. https://www.mayoclinic.org/diseases-conditions/impetigo/symptoms-causes/syc-20352352#:~:text=Impetigo%20

2. MyHealth - Impetigo. http://www.myhealth.gov.my/en/impetigo-2/

3. UpToDate - Impetigo.

4. CDC -  Impetigo: All You Need to Know. https://www.cdc.gov/groupastrep/diseases-public/impetigo.html

5. DermNet NZ - Impetigo https://dermnetnz.org/topics/impetigo/

Cover image credit: DermNet NZ 

Written By

Ms Joyce Toh

Reviewed By

Doc2us Medical Board