A study recently published in the journal mSphere has revealed that hand sanitizers may not be as effective as advertised. The scientists behind the study revealed that most people have been using hand sanitizer the wrong way, reducing its effectiveness.
Hand sanitizers have been a staple in the bags, purses, and pockets of most people since it first made its debut in Europe around 1980. It has been the first thing people reach for after a sneeze, or after blowing their noses.
However, according to the research, hurriedly rubbing on hand sanitizer will not kill the bacteria in one's hands as the mucus is still wet.
The team of Japanese researchers conducted an experiment where hands of 10 volunteers were smeared with wet mucus collected from people who have influenza A. The volunteers were asked to rub on hand sanitizer for up to two minutes where the mucus was dabbed on. Unfortunately, this did not kill the flu virus. Further research and experimentation revealed that hand sanitizer would have to be rubbed on for a full four minutes for it to take effect and kill the virus, making it non-infectious.
Dr. Charles Gerba, a microbiologist and a professor at the University of Arizona pointed out that people typically rub on hand sanitizer for an average of only 11 seconds. The professor later added that people are not applying the disinfectant long enough, leaving the mucus wet and the virus still active.
Dr. Ryohei Hirose, a molecular gastroenterologist at Kyoto Prefectural University of Medicine, Japan and the co-lead author of the study, explained that the reason why manufacturers have advertised hand sanitizers as somewhat "instantly" effective is because of prior research that tested the hand sanitizer on mucus that has already dried out. Dr. Hirose pointed out that for microbes to grow or spread, the mucus had to be wet. The thick consistency of mucus, according to the doctor, is key to the survival of the microbes.
The later phases of the study have revealed that the microbes could be killed within 30 seconds if the hand sanitizer was applied 30 minutes after drying out the mucus.
Dr. Hirose plans to move forward with the research, exploring whether more intense hand rubbing while using hand sanitizer is instrumental in killing the germs.
The said research also revealed the flu-infected mucus, whether wet or dry, could be killed by proper handwashing, which involves using soap and water and scrubbing for 30 to 40 seconds.