Impetigo is an acute superficial bacterial skin infection. It is highly contagious.

The rash presents as oozing or crusted blisters which can be present anywhere on the body but are usually found around the mouth and nose. 
Impetigo is most often caused by staphylococcus aureus or strep pyogenes (Group A strep.). 

Treatment should be as per local antimicrobial guidelines which is usually a narrow spectrum penicillin based antibiotic such as flucloxacillin. 
Good hygiene, use of antibacterial soap and separate towels are also encouraged. 

Symptoms appear 4-10 days after contact with bacteria and usually resolve within 2-3 weeks without scarring. 

Bullous impetigo

Bullous impetigo is a bacterial skin infection caused by staphylococcal aureus resulting in the formation of large blisters known as bullae (>5mm diameter). Generally affects areas with skin folds including armpits, beneath breast, between buttocks, groin, and between fingers and/or toes. 

Bullae are caused by staphylococcal exfoliative toxins (exfoliatin A-D) which targets desmoglein 1 and cleaves off the superficial epidermis through the granular layer, thus separation of the epidermis layer from the dermis layer

Associated symptoms along with bullae formation include itching, swelling of nearby glands, fevers and diarrhoea.

Management involves oral antibiotics for a duration of 7-10 days, although MRSA positive patients may require longer therapy depending on the severity of the infection.