title: Persistent environmental contamination with USA300 methicillin-resistant Staphylococcus aureus and other pathogenic strain types in households with S. aureus skin infections.
abstract: OBJECTIVE
  To understand the genotypic spectrum of environmental contamination of Staphylococcus aureus in households and its persistence.
  
  
  METHODS
  Prospective longitudinal cohort investigation.
  
  
  METHODS
  Index participants identified at 2 academic medical centers.
  
  
  METHODS
  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.
authors.affiliation: Division of Infectious Diseases, Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center, Torrance, California.
authors.forename: Samantha J
authors.initials: SJ
authors.lastname: Eells
authors.forename: Michael Z
authors.initials: MZ
authors.lastname: David
authors.forename: Alexis
authors.initials: A
authors.lastname: Taylor
authors.forename: Nancy
authors.initials: N
authors.lastname: Ortiz
authors.forename: Neha
authors.initials: N
authors.lastname: Kumar
authors.forename: Julia
authors.initials: J
authors.lastname: Sieth
authors.forename: Susan
authors.initials: S
authors.lastname: Boyle-Vavra
authors.forename: Robert S
authors.initials: RS
authors.lastname: Daum
authors.forename: Loren G
authors.initials: LG
authors.lastname: Miller
mesh_terms: D001427:Bacterial Toxins / Q000235:genetics; D015373:Bacterial Typing Techniques; D002641:Chicago; D004269:DNA, Bacterial / Q000032:analysis*; D004783:Environmental Microbiology; D005098:Exotoxins / Q000235:genetics; D005191:Family Characteristics; D050456:Fomites / Q000382:microbiology*; D005838:Genotype; D006798:Housing; D006801:Humans; D007956:Leukocidins / Q000235:genetics; D008137:Longitudinal Studies; D015141:Los Angeles; D055624:Methicillin-Resistant Staphylococcus aureus / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D058885:Multilocus Sequence Typing; D011446:Prospective Studies; D012307:Risk Factors; D013207:Staphylococcal Skin Infections / Q000382:microbiology*; D013997:Time Factors
chemical_list: D001427:Bacterial Toxins; D004269:DNA, Bacterial; D005098:Exotoxins; D007956:Leukocidins; C078284:Panton-Valentine leukocidin