Study reveals how Staph, MRSA spread in households

As a pediatric infectious physician in St. Louis, Stephanie Fritz, MD, sees a fair amount of patients with MRSA skin infections, many of which come back over the course of a year. And she and her colleagues frequently see these infections occurring in multiple members of the same family.

As a researcher who’s been studying MRSA (methicillin-resistant Staphylococcus aureus) for some time, Fritz has been wanting to get to the bottom of this. Staph bacteria is known to reside on the skin of roughly one third of the population, and while it’s well established that Staph infections are transmitted from person to person, the household environment and pets have also been implicated as potential sources. But research on how big a role these factors play in MRSA transmission has been limited.

What Fritz wanted to know was what was driving these within-family infections, and what dynamics were in place. How is MRSA getting into these households in the first place? Were household members getting infected by another family member, from an outside source, or by an item inside the house? What role do pets play? And why was she seeing so many recurrent infections?

“We really wanted to dig deeper,” said Fritz, an associate professor of pediatrics at Washington University in St. Louis (WUSTL) School of Medicine and lead author of a study on Staph transmission published yesterday in The Lancet Infectious Diseases. “We wanted to track these dynamics so that we could identify targets to interrupt transmission and acquisition.”