What type of bacteria causes impetigo?

Impetigo is primarily caused by two types of bacteria: Staphylococcus aureus and Streptococcus pyogenes. Staphylococcus aureus is often responsible for the more common forms of impetigo, while Streptococcus pyogenes can lead to more severe cases. These bacteria infect the skin, typically through cuts or abrasions, leading to the characteristic sores and blisters associated with the condition.