Household Contacts of Children with Staph Infections Appear to Have High Rate of MRSA Colonization

Household contacts of children with Staphylococcus aureus skin and soft tissue infections (SSTI) appeared to have a high rate of methicillin-resistant S aureus (MRSA) colonization compared with the general population, according to a report published in the June issue of Archives of Pediatrics & Adolescent Medicine.
Outbreaks of S aureus can occur within households and asymptomatic S aureus colonization in a household member may be a reservoir for transmission to other household contacts, including children treated for an S aureus infection who may reacquire the organism, according to the study background.
In this study evaluating S aureus colonization in household contacts of pediatric patients with community-associated S aureus SSTI and colonization, we determined that more than half of household contacts were also colonized with S aureus. The prevalence of MRSA colonization (21 percent overall) among these household members was substantially higher than previously published national rates (0.8 percent-1.5 percent) for MRSA colonization in community populations, Stephanie A. Fritz, MD, MSCI, and colleagues from Washington University School of Medicine, St. Louis, report in their cross-sectional study.
The study included 183 patients with community-associated S aureus SSTI and S aureus colonization (in the nose, axilla [armpit] and/or inguinal folds [groin area]) and their household contacts, who were defined as individuals who spent more than half of their time each week in the primary household of the patient. The patients were evaluated at St. Louis Childrens Hospital Emergency Department and ambulatory wound center, as well as from nine community pediatric practices affiliated with a practice-based research network.
Of the 183 patients, 112 (61 percent) were colonized with MRSA; 54 (30 percent) with methicillin-sensitive S aureus (MSSA); and 17 (9 percent) with both MRSA and MSSA. Of 609 household contacts, 323 (53 percent) were colonized with S aureus; 115 (19 percent) with MRSA; 195 (32 percent) with MSSA; and 13 (2 percent) with MRSA and MSSA, according to study results.
Parents were more likely than other household contacts to be colonized with MRSA, the results indicate. Also, the authors note that the inguinal fold (groin area) was a prominent site of MRSA colonization.
Household contacts of patients with S aureus infections are not routinely sampled for S aureus colonization, and failure to identify all colonized household members may facilitate persistent colonization or recurrent infections. In addition, household environmental surfaces and shared objects represent potential reservoirs for S aureus transmission. However, there are no data to indicate whether routine household sampling or decolonization would be practical or cost-effective, the authors conclude.

Reference: Arch Pediatr Adolesc Med. 2012;166[6]:551-557.