Limited Adaptation of <i>Staphylococcus aureus</i> during Transition from Colonization to Invasive Infection
Anna K. Räz, Federica Andreoni, Mathilde Boumasmoud, Judith Bergadà-Pijuan, Tiziano A. Schweizer, Srikanth Mairpady Shambat, Barbara Hasse, Annelies S. Zinkernagel, Silvio D. Brugger
Abstract
S. aureus is a major pathogen of humans, causing a wide range of diseases. The difficulty to develop a vaccine and antibiotic treatment failure warrant the exploration of novel treatment strategies. Asymptomatic colonization of the human nasal passages is a major risk factor for invasive disease, and decolonization procedures have been effective in preventing invasive infections. However, the transition of S. aureus from a benign colonizer of the nasal passages to a major pathogen is not well understood, and both host and bacterial properties have been discussed as being relevant for this behavioral change. We conducted a thorough investigation of patient-derived strain pairs reflecting colonizing and invasive isolates in a given patient. Although we identified limited genetic adaptation in certain strains, as well as slight differences in adherence capacity among colonizing and invasive isolates, our work suggests that barrier breaches are a key event in the disease continuum of S. aureus.