title: Escherichia coli colonization patterns among human household members and pets, with attention to acute urinary tract infection.
abstract: BACKGROUND
  Within-household transmission of Escherichia coli may promote urinary tract infection (UTI) but is poorly understood.
  
  
  METHODS
  Fecal samples from 228 individuals (152 humans [5 with acute UTI] and 76 pets) in 63 households were extensively processed for unique E. coli clones, as defined by random-amplified polymorphic DNA analysis and pulsed-field gel electrophoresis. Patterns of strain sharing (presence of a clone in multiple individuals) were assessed.
  
  
  RESULTS
  Of 335 E. coli clones, 90 (27%) were recovered from multiple hosts (up to 11 per clone). Within-household strain sharing (1) involved 68% of households, including 3 of 5 households in which a member had a UTI; (2) was more frequent than across-household strain sharing (27% vs. 0.8% of potential sharing pairs; P< .001); (3) increased with household size (r2=0.93; P< .001); and (4) varied by host-pair type (pet-pet, 58%; human-human, 31%; human-pet, 17%). Sex partners shared strains more commonly than did other adults (31% vs. 7% of pairs; P= .08) but accounted for only 12% of within-household strain sharing.
  
  
  CONCLUSIONS
  Within-household sharing of E. coli, including in households in which a member has a UTI, is common and can involve any combination of humans and pets. Identification of the underlying mechanism(s) could lead to novel preventive measures against UTI.
authors.affiliation: Mucosal and Vaccine Research Center, Minneapolis Veterans Affairs Medical Center, Minnesota, Minneapolis 55417, USA. johns007@umn.edu
authors.forename: James R
authors.initials: JR
authors.lastname: Johnson
authors.forename: Krista
authors.initials: K
authors.lastname: Owens
authors.forename: Abbey
authors.initials: A
authors.lastname: Gajewski
authors.forename: Connie
authors.initials: C
authors.lastname: Clabots
mesh_terms: D000208:Acute Disease; D000328:Adult; D000818:Animals; D000829:Animals, Domestic / Q000382:microbiology*; D002415:Cats; D002648:Child; D002675:Child, Preschool; D004285:Dogs; D016521:Electrophoresis, Gel, Pulsed-Field; D004926:Escherichia coli / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D004927:Escherichia coli Infections / Q000453:epidemiology* / Q000382:microbiology / Q000635:transmission; D005191:Family Characteristics; D005243:Feces / Q000382:microbiology*; D005260:Female; D006801:Humans; D008297:Male; D015995:Prevalence; D019105:Random Amplified Polymorphic DNA Technique; D014552:Urinary Tract Infections / Q000453:epidemiology* / Q000382:microbiology / Q000635:transmission