It is due to either Staphylococcus aureus or Streptococcus pyogenes.[3]


Because impetigo is caused by a bacterium that is transmitted onto the skin, it is contagious and easily contracted by persons who might touch the affected person.

Impetigo is a bacterial infection that involves the superficial skin.


Risk factors include attending daycare, crowding, poor nutrition, diabetes, contact sports, and breaks in the skin such as from mosquito bites, eczema, scabies or herpes.[3][4] With contact it can spread around or between people. Diagnosis is typically based on the symptoms.[3]

Treatment is typically with antibiotic creams such as mupirocin or fusidic acid.[3][5] Antibiotics by mouth, such as cephalexin, may be used if large areas are affected.[3] Antibiotic resistant forms have been found.[3]

Impetigo affected about 140 million people (2% of the world population) in 2010.[6] It is most common in young children but can occur at any age. Without treatment people typically get better within three weeks. Complications may include cellulitis or poststreptococcal glomerulonephritis.[3] The condition is also known as "school sores".[1] The name is from the Latin impetere meaning "attack".[7]

OSC Microbio 21 02 impetigo.jpg



 Treatment involves the use of antibiotics.


Prevention is by handwashing, avoiding people who are infected, and cleaning injuries.[1]

Most people with pyelonephritis do not have complications if appropriately treated with bacteria-fighting medications called antibiotics.

In rare cases, pyelonephritis may cause permanent kidney scars, which can lead to chronic kidney disease, high blood pressure, and kidney failure. These problems usually occur in people with a structural problem in the urinary tract, kidney disease from other causes, or repeated episodes of pyelonephritis.

Infection in the kidneys may spread to the bloodstream—a serious condition called sepsis—though this is also uncommon.



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