WHO's DIY sanitizer recipes work, but you need to use them for 30 seconds to kill COVID-19 virus, study shows
World Health Organization's recipes for making hand sanitizers work perfectly well and effectively kill the new coronavirus, according to early findings from a new study.
Still, handwashing with soap and water for 20 seconds is the best way to keep the virus at bay. But if you do not have access to them and your neighborhood stores run out of commercial sanitizers, you can make your own by following the WHO's alcohol-based recipes. According to the Centers for Disease Control and Prevention (CDC), sanitizers that contain more than 60% alcohol are effective.
With no approved drugs against the virus and vaccines, experts think hand hygiene is key to staying safe. "Virus containment and prevention of infection are the current highest priorities. To limit virus spread, effective hand hygiene is crucial. Therefore, easily available but efficient disinfectants are needed," the authors wrote in their preprint study.
To that end, the WHO came up with two alcohol-based recipes that differ only by one ingredient, alcohol. There is ethanol in the first recipe and isopropanol in the second one. However, the two formulations share other ingredients: hydrogen peroxides, glycerol and sterilized distilled water. You can find the WHO's formulation here.
In this study, a team of researchers from Switzerland and Germany tested the two WHO's concoctions against the new coronavirus. They also evaluated whether individual ingredients such as alcohol — ethanol and isopropanol — kill the virus, which has sickened more than 2.4M people globally. More than 165,000 people are dead, according to Johns Hopkins University.
So, the team exposed the virus to different concentrations of these concoctions for 30 seconds, as recommended by the WHO. They found that both the formulations acted against the virus but the isopropanol-based sanitizer was a more efficient killer because it was capable of destroying the virus even at low concentrations.
What is more, the virus was susceptible to individual components — ethanol and isopropanol. Furthermore, the team observed that the virus gets completely inactivated when it comes into contact with either alcohol types at a low 30% concentration for 30 seconds.
"Our findings are therefore of utmost importance in the current outbreak situation to minimize viral transmission and maximize virus inactivation," the authors wrote in their study, adding that they endorse alcohol-based sanitizers.
Though effective, WHO's recipes have a limitation. They take 30 seconds to kill the virus, making them impractical to use. "The defined inactivation time of exactly 30s, which is the time recommended but not routinely performed in practice," say the authors of the study.
It is also important to remember that alcohols work as sanitizers and when ingested. Addressing a myth, the WHO said that drinking alcohol does not kill the virus. It added: "Consuming alcohol will not destroy the virus, and its consumption is likely to increase health risks if a person becomes infected with the virus. Alcohol (at a concentration of at least 60% by volume) works as a disinfectant on your skin, but it has no such effect within your system when ingested."