A stethoscope is an essential diagnostic tool in a physician’s armamentarium. It is also the most recognizable sign of the medical profession. But, now they are gaining another new identity, as potential routes of infection transmission.

Failure of stethoscope hygiene is becoming a common cause of transmission of infection. Evidence shows stethoscopes as capable of also transmitting potentially resistant bacteria, including methicillin-resistant Staphylococcus aureus (MRSA).

A new study published online Dec. 12, 2018 in the Infection Control & Hospital Epidemiology has added to the growing evidence of stethoscopes as carriers of infection.

The study found that stethoscopes carried by doctors in an ICU, which are used on multiple patients, are significantly contaminated with a rich and diverse community of bacteria that includes organisms associated with healthcare-associated infections (HAIs). And, among these, Staphylococcus was ubiquitous and had the highest relative abundance. On a set of 40 stethoscopes in use in an ICU, all 40 had a high abundance of Staphylococcus bacteria, with "definitive" S. aureus bacteria present on 24 of 40 stethoscopes tested.

The study also investigated the impact of cleaning on bacterial contamination but the results were not very encouraging. While cleaning of stethoscopes – by either standardized or practitioner-preferred methods - did reduce bacterial contamination levels, but the levels of clean stethoscopes were attained only in few cases.

Stethoscopes become contaminated after each patient use. Hence, the Centers for Disease Control and Prevention (CDC) recommends that re-usable medical equipment, such as stethoscopes, must undergo disinfection between patients.

This study reiterates the need for strict infection control practices and adhering to recommended guidelines for decontamination procedures in between patients. Or, single-patient-use stethoscopes can be used to prevent cross contamination.

(Source: Medscape; Infection Control & Hospital Epidemiology. 2018; DOI:10.1017/ice.2018.319)

Dr KK Aggarwal

Padma Shri Awardee

President Elect Confederation of Medical Associations in Asia and Oceania   (CMAAO)

Group Editor-in-Chief IJCP Publications

President Heart Care Foundation of India

Immediate Past National President IMA