While doctors and other medical professionals tend to put a great deal of emphasis on cleanliness and hand washing, a new study indicates that the number one tool that a doctors uses to interact with patients – a stethoscope – may actually hold more germs than his or her hands.
Surprisingly, the new report says that a typical stethoscope is generally cleaned less than once a month – if it gets cleaned at all.
The University of Geneva research team who conducted the study found that stethoscopes often hold just as much bacteria as the palms of doctors’ hands with only the tips of the fingers holding more.
Among the bacteria being harbored on the instruments were MRSA (methicillin-resistant Staphylococcus aureus), a type of bacteria that is often implicated in hospital-acquired infections. MRSA infections are very difficult to treat – and potentially life threatening – due to the fact that they are resistant to currently-existing antibiotics.
For the study, Dr. Didier Pittet and the team of Swiss researchers took measurements of bacteria collected after patient examinations. Three doctors, as well as 83 patients, were involved in the study. Samples were taken from four places on the doctors’ hands, including the fingertips, back of the hand and two locations on the palm. The samples were taken from each doctor’s dominant hand. Two spots on the stethoscopes were sampled: the diaphragm (the flat, round part of the stethoscope that gets pressed against the patient’s skin) and the tube connecting the diaphragm to the earpieces. The measurements were taken after 71 patients had been examined. The doctors wore sterile gloves and the stethoscopes were sterilized before the patient examinations began.
Not too surprisingly, the fingertips had the most bacteria on them. They were found to have 467 aerobic colony counts and 12 MRSA colony-forming units, which are both measures of bacterial contamination.
The diaphragms of the stethoscopes, however, had the second-highest counts. They had 89 aerobic colony counts and seven MRSA colony-forming units. By contrast, the area on the palm under the little finger had only 32 aerobic colony counts and two MRSA colony-forming units.
The researchers did not attempt to isolate any other types of bacteria.
Based upon these results, Dr. Pittet says that stethoscopes, which tend to come into contact with many different patients during the day, should be considered as a potential means for harmful bacterial infections to be transmitted between patients. He suggests that in order to control this risk that stethoscopes should be considered an extension of a doctor’s hands, getting cleaned and disinfected between patients.
The study authors say that more research is needed to answer such questions as what is the best method for disinfecting stethoscopes, how long bacteria can survive on them and how bacteria are transmitted onto someone’s skin.
According to the British Medical Association, there is no evidence that any infections have actually been transmitted via stethoscopes.
The study dealing with doctors’ stethoscopes and they germs that they hold was published on Thursday in the medical journal Mayo Clinic Proceedings.
By Nancy Schimelpfening