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.
The reason: When wet mucus surrounds the virus, it acts as a protective hydrogel, keeping the disinfectant from reaching and killing the germs. 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 authors of the study, which was published earlier this week in the journal mSphere, say they were somewhat surprised by their results. Previous studies have suggested ethanol-based sanitizers are effective against flu viruses.
“We had predicted that the virus in mucus would be somewhat resistant to alcohol disinfectants,” said Dr. Ryohei Hirose, the study’s lead author and a molecular gastroenterologist at Kyoto Profectural University of Medicine, in an interview with Healthline. “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.”