BALTIMORE (WJZ) — Stethoscopes can give you more than just a cold shiver when placed on your skin, as they can carry viruses when they are not cleaned.

And, according to a study from the Yale School of Medicine, doctors rarely, if ever, sterilize their stethoscopes between uses.

Over a four week stint, researchers studied one medical staff’s tendencies with their instruments. Researchers found that stethoscopes weren’t sterilized even one time while observing medical students, attending physicians and resident physicians.

“Stethoscopes are used repeatedly throughout the day and become contaminated after each patient exposure, so they must be treated as potential vectors of transmission,” said Linda Greene, researcher and president of the Association for Professionals in Infection Control and Epidemiology, via a press release. “Failing to disinfect stethoscopes could constitute a serious patient safety issue similar to ignoring hand hygiene.”

After the initial observation, researchers lectured the staff on the importance of cleaning their instruments. The researchers then found that few changed their ways in a follow up.

“Standard education may not be the answer to this problem,” the study read. “Behavioral and cultural modification to improve hand hygiene still remains a challenge, despite being studied in large randomized trials. Stethoscope hygiene implementation will need more consistent efforts to change culture and habits.”

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