Clonality of Staphylococcus aureus Colonization over Time in Attendees of a Camp for Children with Chronic Dermatoses

Abstract

Chronic dermatoses are risk factors for Staphylococcus aureus colonization; little is known about the significance of transmission between persons with chronic dermatoses (CD) and their contacts. We collected nasal, axillary, and skin swabs for S. aureus from 50 attendees of a camp for children with CD and their families at three time points: start and end of 2005 camp and start of 2006 camp (times A, B, and C, respectively). Thirty-one persons had CD, including epidermolysis bullosa (n = 14), atopic dermatitis (n = 7), ichthyosis (n = 5), and psoriasis (n = 5). Methicillin susceptibility and genotype were determined for all S. aureus isolates. Seventy-one unique S. aureus isolate from 10 clonal complexes (CC) were isolated; 14 (20%) were methicillin-resistant (MRSA). Persons with CD were more likely than those without CD to be colonized with S. aureus at the start of the 2005 (p = 0.01) and 2006 (p = 0.02) camp or at any time or site (p = 0.04) or to be persistently colonized with the same S. aureus CC at the start and end of the 2005 camp. Persons with atopic dermatitis had the highest burden of S. aureus colonization, whereas MRSA was isolated most frequently from attendees with epidermolysis bullosa. Three hospitalizations for skin infections were noted in people with CD between the 2005 and 2006 camps, versus three hospitalizations in the 6 months before the 2005 camp. Although S. aureus colonization was frequent among camp attendees (and in persons with CD in particular), it was diverse and variable. Camp attendance did not appear to affect infection-related clinical outcomes.