The Centers for Disease Control and Prevention (CDC) recommends that you follow these five simple steps when washing your hands: In contrast, when the volunteers washed off the mucus by rubbing their hands together under running water - without soap - the flu virus was eradicated within 30 seconds, regardless of whether the mucus was dry or wet. When the mucus was wet, however, it took eight times longer - about four minutes. When the mucus was dry, the sanitizer took about 30 seconds to inactivate the virus. The researchers then applied a hand sanitizer to the volunteers’ fingers - either after the mucus completely dried (a process that took about 40 minutes) or while it was still wet. “We aimed to reproduce the situation in which infectious mucus discharged from patients adheres to the fingers of medical staff,” they explain.
The new study involved a series of tests in which Hirose and his colleagues took sputum (a mixture of coughed-up saliva and mucus) from people infected with influenza A virus (the most common type of flu virus) and put it on the fingertips of 10 volunteers. In those studies, the disinfectant was able to reach and inactivate the virus within half a minute or so. Most of the earlier studies, Hirose and his co-authors point out in their paper, were conducted using virus-containing solutions that had already dried. “However, we found that the protective effect of mucus is stronger than expected and there may be room for improvement in current hand hygiene guidelines.” Ryohei Hirose, the study’s lead author and a molecular gastroenterologist at Kyoto Profectural University of Medicine, in an interview with Healthline.
“We had predicted that the virus in mucus would be somewhat resistant to alcohol disinfectants,” said Dr. Previous studies have suggested ethanol-based sanitizers are effective against flu viruses. The authors of the study, which was published earlier this week in the journal mSphere, say they were somewhat surprised by their results. But when you wash with running water, the rubbing action of your hands (if you do it thoroughly) removes the mucus and washes the virus down the drain. The reason: When wet mucus surrounds the virus, it acts as a protective hydrogel, keeping the disinfectant from reaching and killing the germs. Washing your hands under running water - even without soap - is more effective at stopping the spread of flu germs than using ethanol-based hand sanitizers, according to Japanese researchers.