International Scientific Forum on Home Hygiene

Home Hygiene & Health

The Leading Source of Scientific, Professional & Consumer Information
International Scientific Forum on Home Hygiene

Home Hygiene & Health

The Leading Source of Scientific, Professional & Consumer Information

Persistent environmental contamination with USA300 methicillin-resistant Staphylococcus aureus and other pathogenic strain types in households with S. aureus skin infections

OBJECTIVE: To understand the genotypic spectrum of environmental contamination of Staphylococcus aureus in households and its persistence. DESIGN: Prospective longitudinal cohort investigation. SETTING: Index participants identified at 2 academic medical centers. PARTICIPANTS: Adults and children with S. aureus skin infections and their household contacts in Los Angeles and Chicago. METHODS: Household fomites were surveyed for contamination at baseline and 3 months. All isolates underwent genetic typing. RESULTS: We enrolled 346 households, 88% of which completed the 3-month follow-up visit. S. aureus environmental contamination was 49% at baseline and 51% at 3 months. Among households with a USA300 methicillin-resistant S. aureus (MRSA) body infection isolate, environmental contamination with an indistinguishable MRSA strain was 58% at baseline and 63% at 3 months. Baseline factors associated with environmental contamination by the index subject's infection isolate were body colonization by any household member with the index subject's infection isolate at baseline (odds ratio [OR], 10.93 [95% confidence interval (CI), 5.75-20.79]), higher housing density (OR, 1.47 [95% CI, 1.10-1.96]), and more frequent household fomite cleaning (OR, 1.62 [95% CI, 1.16-2.27]). Household environmental contamination with the index subject's infection strain at 3 months was associated with USA300 MRSA and a synergistic interaction between baseline environmental contamination and body colonization by any household member with the index subject's infection strain. CONCLUSIONS: We found that infecting S. aureus isolates frequently persisted environmentally in households 3 months after skin infection. Presence of pathogenic S. aureus strain type in the environment in a household may represent a persistent reservoir that places household members at risk of future infection. Infection Control and Hospital Epidemiology : The Official Journal of the Society of Hospital Epidemiologists of America, 35(11), 1373–82. http://doi.org/10.1086/678414