Chances are you've heard of MRSA, which is the kind of staph that isn't susceptible to methicillin, the antibiotic that used to be a silver bullet.
Staph is happy to live on your skin or up your nose. A person can harbor the bacteria and wind up spreading them without showing any signs of infection. A third of peoplecarry staph in their noses, according to studies cited by the Centers for Disease Control and Prevention. About 2 percent of people carry MRSA.
The researchers also took weekly bacterial samples from the people's noses and used genetic tests to fingerprint the staph. That way the scientists could trace the movement of bacteria from person to person.
The scheme worked.
Over four months of tracking and testing, the researchers mapped the hops that bacteria made from one person to another to another. They documented 173 transmissions of staph between people in the study. About a third of patients who had been free of staph when admitted were colonized within a month.