These days, enhanced hand washing is the new normal, and hand sanitizer became a must-have item. And while there is no denying the benefit of a single squirt of the solution to your hand contamination, one new survey says we tend to underestimate how long it takes for the product to do its job. As it turns out, you’ll need to wait a full four minutes for alcohol-based sanitizers to eliminate viral particles, making regular handwashing seem a little more convenient after all.
The Japanese study, which was recently published in the journal mSphere, shows that for hand sanitizers to be effective and work properly, one must continuously rub their hands for four minutes. The reasoning behind it is that the viral particles are protected from the product’s active ingredients by a thin layer of mucus, which takes time to break down. As a result, and as the study explains, these findings make most hand sanitizing guidelines insufficient. The study reads: “Current hand hygiene methods recommended by the CDC and WHO involve the use of disinfectants… for 15 to 30 seconds. However, our results suggest that this disinfection time is insufficient for the disinfection of infectious mucus.”
The research team found that the hand sanitizer presented yet another challenge – the product doesn’t work until mucus is completely dry. Meaning that for 30 minutes after your hands are contaminated, the viral particles can no longer be inactivated by sanitizer and remain transmissible. Traditional water and soap hand-washing, on the other hand, can be done at any point after contamination and takes just 30 seconds to work effectively. Soap quickly dissolves the lipid layer that protects viral particles and destroys the particles themselves, then washes away any leftover microorganisms as you rinse. So, while you should probably still keep sanitizer handy for those instances where there’s no sink in sight, soap and water should be your go-to solution whenever possible. And when you do use a hand sanitizer, make sure to apply a generous amount and rub it for four full minutes. Take care and remain safe!