MSSA is a kind of Staphylococcus aureus — a common round bacteria that lives on skin and in noses, and can make people ill if it gets into a cut, a wound, or the blood. The letters stand for methicillin-susceptible Staphylococcus aureus (some doctors say sensitive instead of susceptible). The important word is susceptible: ordinary antibiotic drugs, including the old drug methicillin, can still kill it. You will mostly meet MSSA in hospital notes, often next to its famous cousin MRSA. Both show up in hospitals. Both can be serious. Though actually, the tidy line that lumps MSSA with 'superbugs that drugs cannot touch' is mixing it up with MRSA. MRSA is the one that shrugs off those ordinary drugs. MSSA does not. Doctors still take MSSA seriously — it can still make you very sick — but the treatment is different. It does not specially 'attack the nervous system' as its main job. Like other staph, it more often hits skin, wounds, lungs, or the blood. If an infection spreads far, many parts of the body can suffer, but that is not what the name is about.