title: Contamination of stethoscopes and physicians' hands after a physical examination.
abstract: OBJECTIVE
  To compare the contamination level of physicians' hands and stethoscopes and to explore the risk of cross-transmission of microorganisms through the use of stethoscopes.
  
  
  METHODS
  We conducted a structured prospective study between January 1, 2009, and May 31, 2009, involving 83 inpatients at a Swiss university teaching hospital. After a standardized physical examination, 4 regions of the physician's gloved or ungloved dominant hand and 2 sections of the stethoscopes were pressed onto selective and nonselective media; 489 surfaces were sampled. Total aerobic colony counts (ACCs) and total methicillin-resistant Staphylococcus aureus (MRSA) colony-forming unit (CFU) counts were assessed.
  
  
  RESULTS
  Median total ACCs (interquartile range) for fingertips, thenar eminence, hypothenar eminence, hand dorsum, stethoscope diaphragm, and tube were 467, 37, 34, 8, 89, and 18, respectively. The contamination level of the diaphragm was lower than the contamination level of the fingertips (P<.001) but higher than the contamination level of the thenar eminence (P=.004). The MRSA contamination level of the diaphragm was higher than the MRSA contamination level of the thenar eminence (7 CFUs/25 cm(2) vs 4 CFUs/25 cm(2); P=.004). The correlation analysis for both total ACCs and MRSA CFU counts revealed that the contamination level of the diaphragm was associated with the contamination level of the fingertips (Spearman's rank correlation coefficient, ρ=0.80; P<.001 and ρ=0.76; P<.001, respectively). Similarly, the contamination level of the stethoscope tube increased with the increase in the contamination level of the fingertips for both total ACCs and MRSA CFU counts (ρ=0.56; P<.001 and ρ=.59; P<.001, respectively).
  
  
  CONCLUSIONS
  These results suggest that the contamination level of the stethoscope is substantial after a single physical examination and comparable to the contamination of parts of the physician's dominant hand.
authors.affiliation: Infection Control Program and WHO Collaborating Centre on Patient Safety, University of Geneva Hospitals, Geneva, Switzerland; Faculty of Medicine, University of Geneva, Geneva, Switzerland.
authors.forename: Yves
authors.initials: Y
authors.lastname: Longtin
authors.affiliation: Infection Control Program and WHO Collaborating Centre on Patient Safety, University of Geneva Hospitals, Geneva, Switzerland; Faculty of Medicine, University of Geneva, Geneva, Switzerland.
authors.forename: Alexis
authors.initials: A
authors.lastname: Schneider
authors.affiliation: Infection Control Program and WHO Collaborating Centre on Patient Safety, University of Geneva Hospitals, Geneva, Switzerland; Faculty of Medicine, University of Geneva, Geneva, Switzerland.
authors.forename: Clément
authors.initials: C
authors.lastname: Tschopp
authors.affiliation: Bacteriology Laboratory and Genomic Research Laboratory, University of Geneva Hospitals, Geneva, Switzerland.
authors.forename: Gesuèle
authors.initials: G
authors.lastname: Renzi
authors.affiliation: Infection Control Program and WHO Collaborating Centre on Patient Safety, University of Geneva Hospitals, Geneva, Switzerland; Faculty of Medicine, University of Geneva, Geneva, Switzerland.
authors.forename: Angèle
authors.initials: A
authors.lastname: Gayet-Ageron
authors.affiliation: Bacteriology Laboratory and Genomic Research Laboratory, University of Geneva Hospitals, Geneva, Switzerland.
authors.forename: Jacques
authors.initials: J
authors.lastname: Schrenzel
authors.affiliation: Infection Control Program and WHO Collaborating Centre on Patient Safety, University of Geneva Hospitals, Geneva, Switzerland; Faculty of Medicine, University of Geneva, Geneva, Switzerland. Electronic address: didier.pittet@hcuge.ch.
authors.forename: Didier
authors.initials: D
authors.lastname: Pittet
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001420:Bacteria, Aerobic / Q000302:isolation & purification*; D001424:Bacterial Infections / Q000517:prevention & control / Q000635:transmission; D015169:Colony Count, Microbial; D003428:Cross Infection / Q000635:transmission*; D004866:Equipment Contamination; D005260:Female; D006225:Hand / Q000382:microbiology*; D006784:Hospitals, Teaching; D006801:Humans; D008297:Male; D055624:Methicillin-Resistant Staphylococcus aureus / Q000302:isolation & purification*; D008875:Middle Aged; D010808:Physical Examination / Q000379:methods / Q000592:standards; D011446:Prospective Studies; D012306:Risk; D013203:Staphylococcal Infections / Q000517:prevention & control / Q000635:transmission; D019023:Stethoscopes / Q000382:microbiology*