title: Fecal carriage rates of extended-spectrum β-lactamase-producing Escherichia coli among antibiotic naive healthy human volunteers.
abstract: BACKGROUND
  Higher prevalence of extended-spectrum β-lactamase (ESBL)-producing Escherichia coli fecal carriage has been reported in the nosocomial setting than in the community. We tried to determine the fecal carriage of ESBL-producing E. coli among healthy volunteers in a relatively isolated community.
  
  
  METHODS
  This study was conducted on 115 healthy adult volunteers from whom one fecal sample was collected and was plated on selective media. Each morphotypes were identified, characterized, and ESBL phenotype was confirmed by double-disk potentiation method. Molecular characterization of ESBL gene was done using multiplex polymerase chain reaction and pulse-field gel electrophoresis (PFGE) was done to identify their clonal relation.
  
  
  RESULTS
  ESBL-producing E. coli had a prevalence of 19% (22/115) among the healthy volunteers in the community. CTX-M was the predominant type, showed a presence 95.5% (21/22), TEM 63%, SHV 9%, and both TEM and CTX-M were present in 63.6% (14/22), all three present in 4.5% (1/22). The lineage using PFGE showed a single clone in 17 isolates. Seven isolates were type A (all TEM & CTX-M), six were type A1 (all TEM & CTX-M except 2), four were type A2 (all CTX-M), and three belonged to types B, C, and D respectively Conclusion: High prevalence rate of 19% in the community indicated by this study implies the possibility of sustained ESBL carriage even among isolated population, which could serve as a reservoir for enriching the ESBL pool in the hospital. Clonal relations also indicate a possible epidemiological source that needs to be evaluated.
authors.affiliation: 1 Apollo Institute of Medical Sciences and Research , Hyderabad, India .
authors.forename: Dilip
authors.initials: D
authors.lastname: Mathai
authors.forename: Vasudevan Anil
authors.initials: VA
authors.lastname: Kumar
authors.forename: Breezy
authors.initials: B
authors.lastname: Paul
authors.forename: Madhan
authors.initials: M
authors.lastname: Sugumar
authors.forename: Kamala Russel
authors.initials: KR
authors.lastname: John
authors.forename: Anand
authors.initials: A
authors.lastname: Manoharan
authors.forename: Lalitha Mukkai
authors.initials: LM
authors.lastname: Kesavan
mesh_terms: D000328:Adult; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D058070:Asymptomatic Diseases; D002353:Carrier State / Q000382:microbiology*; D002999:Clone Cells; D017714:Community-Acquired Infections / Q000453:epidemiology / Q000382:microbiology; D003428:Cross Infection / Q000453:epidemiology / Q000382:microbiology; D004197:Disease Reservoirs; D016521:Electrophoresis, Gel, Pulsed-Field; D004926:Escherichia coli / Q000201:enzymology / Q000302:isolation & purification*; D004927:Escherichia coli Infections / Q000453:epidemiology / Q000382:microbiology* / Q000635:transmission; D029968:Escherichia coli Proteins / Q000235:genetics / Q000302:isolation & purification*; D005243:Feces / Q000382:microbiology*; D006801:Humans; D007194:India / Q000453:epidemiology; D015995:Prevalence; D012424:Rural Population; D018440:beta-Lactam Resistance / Q000235:genetics; D001618:beta-Lactamases / Q000235:genetics / Q000302:isolation & purification*; D047090:beta-Lactams / Q000494:pharmacology
chemical_list: D000900:Anti-Bacterial Agents; D029968:Escherichia coli Proteins; D047090:beta-Lactams; D001618:beta-Lactamases