Many people will choose to use alcohol for disinfection in the current epidemic, but the higher the concentration of alcohol is not the better. The effectiveness of alcohol depends on the concentration of ethanol in it. The mechanism by which ethanol kills viruses is that its lipid solubility destroys biofilms composed of biological phospholipid bilayers, causing structural and functional disorders of biofilms, and 75% alcohol is the most effective disinfectant. If the concentration of alcohol is too high, the disinfection effect is not good instead. Therefore, when using alcohol for disinfection, it is not advisable to spray a large area and to avoid open flames.