Focus: methicillin-resistant Staphylococus aureus (MRSA). Introduction.

摘要

Staphylococcus aureus is a non-motile, gram-positive cocci that colonizes in clusters. It is found world wide and is a leading cause of disease. It can normally only transiently colonize the outside and entry portals of the human body (skin, ears, eye, nasal passages, etc.), but it is estimated that 20% of humans are carriers (asymptomatic permanent colonization). However, even transient colonization can lead to infection if the conditions are right; such as a breach in the protective layer of epithelial cells, or a compromised immune system. The ability to cause disease is via two mechanisms: 1) toxin production, and/or 2) proliferation of the organism, which causes tissue destruction.