How many seconds should be used to disinfect hands with alcohol to ensure safety?

The article was professionally consulted with Doctor Tran Quoc Tuan - Emergency Medicine Doctor - Emergency Resuscitation Department - Vinmec Phu Quoc International General Hospital.

The World Health Organization recommends that the most effective and simple way to prevent covid-19 is to wash your hands. Therefore, everyone should disinfect their hands with alcohol with products of clear origin and tested before being put on the market.

Disinfection is the process of killing or eliminating all forms of living microorganisms including bacterial spores.

Non-aqueous handwashing with an alcohol-based solution should only be used when hand washing with soap and water is not possible, but only when hands are not visibly soiled. If hands are visibly dirty, they should be washed regularly (using plain soap (water or cake) to wash hands).

Alcohol 70 degrees for better bactericidal effect than alcohol 90 degrees. Because the 90 degree alcohol just applied to the hand evaporates very quickly, there is not enough time on the hand to kill bacteria. And alcohols below 60 degrees are not guaranteed to disinfect. Alcohol 70 degrees is alcohol with a slower rate of evaporation, just enough time to kill bacteria. In short, do not use alcohol at a high concentration of 90% because it evaporates quickly, does not guarantee contact time and safety.
The US Centers for Disease Control and Prevention (CDC) has also recommended that people protect themselves by washing their hands with soap and clean water, this is the first choice because this method helps reduce all kinds of germs. Only if soap and water are not available should use a quick hand sanitizer with at least 60% alcohol.

When using alcohol-based hand sanitizers or using alcohol to wash your hands quickly, you need to do it for at least 30 seconds, rub and make sure all areas of your hands are in contact with the sanitizer and let dry naturally. The virus will be inactivated after about 3-4 minutes of using this solution. Therefore, it should be noted that within 3-4 minutes after performing quick hand washing, the virus on hands has not been completely destroyed, so it can still be transmitted to others.
However, the contact time and the amount of disinfectant also greatly determine the ability to kill bacteria. Therefore, it is really necessary to strictly follow the instructions for use of each type of solution. For example, the same main ingredient is Ethanol (alcohol) but different products will have different uses. Products commonly used in hospitals such as: Aniosgel 85 NPC can kill virus strains such as Herpes Virus, Rotavirus, Coronavirus within 30 seconds (under standard conditions) with instructions for use of 3ml/30 seconds, with Asirub solution is instructed to use 3-4 ml in 1 minute, Alphasept handrub should use 3ml with a minimum contact time on the hand 30 seconds... At the same time, to calculate the dose, the manufacturer it is necessary to design dosing pumps for each product whereby each pump will pump out a sufficient amount for one hand wash.

Hand sanitizer solution: containing 2-4% chlorhexidine or 5-7% povidone iodine or 1% triclosan... used in surgical hand washing. The types of antiseptic solutions being used at the hospital are Microshield 2% and 4% (used in the operating room). Non-aqueous disinfectants may contain one of the following chemicals: Alcohol (alcohol), Chlorhexidine, Chlorine, Hexachlorophene, Iodine, Para Chloro Meta Xylenol, quaternary ammonium compounds, and Triclosan, often with skin conditioners. In fact, the main ingredients of medical hand sanitizers in general and dry hand sanitizers in particular today often include: ethanol solution (alcohol), purified water, sodium lactate (a type of desiccant). , fragrance (fragrance or essential oils for fragrance), benzalkonium chloride (bactericide)... According to doctors, quick hand sanitizer or dry hand sanitizer has the ability to quickly kill bacteria. , viruses, pathogens that are harmful to health, making them unable to grow and protect clean hands. Some hand sanitizers and alcohol-based hand sanitizers may also contain some nutrients and vitamins to help soften hands.

Step 1: Take 3-5 ml of hand sanitizer in the palm of your hand. Step 2: Rub your hands vigorously for 1 minute, rub your palms together and rub one palm on the back of the other and vice versa. Step 3: Rub your palms together, squeezing your fingers firmly between your fingers. Rub the backs of these fingers on the palm of the other hand and continue to do the opposite (the back of the hand is cupped to match the palm). Step 4: Rub the thumb of one hand against the palm of the other and vice versa (palm hugs the thumb). Rub the tips of these fingers into the palm of the other hand and vice versa. Note: When you complete step 4 but your hands are still not dry, repeat steps 2 to 4 until your hands are dry.
On the other hand, the Ministry of Health recommends that people should not choose quick hand sanitizer products of unknown origin and not tested before being put on the market because they do not guarantee safety and kill ability. bacteria.