Impetigo is a highly contagious skin infection that is most commonly caused by Group A streptococcus and Staphylococcus aureus bacteria. These bacteria often inhabit the skin and mucous membranes without causing any problems, but under certain conditions they can cause impetigo.
The hallmark sign of impetigo is the presence of honey-colored crusts on the skin. The lesions may be small or large, and may occur anywhere on the body. Impetigo may be accompanied by systemic symptoms such as fever, malaise, and swollen lymph nodes.