COVID-19: UpdateStudies: Hand Sanitizers Kill COVID-19 Virus, E-Consults Appropriate
In a study yesterday in Emerging Infectious Diseases, Swiss and German researchers found that alcohol-based hand sanitizers recommended by the World Health Organization (WHO) are effective in killing the novel coronavirus. The authors noted that while 30 seconds is the recommended time to rub hand sanitizers into the skin and was the time used in this study, most people don’t use them for that long. And a study yesterday in the Annals of Internal Medicine with important COVID-19 ramifications found that 70.2 percent of 6,512 electronic consultations (e-consults) made by 1,096 referring clinicians to 121 specialists were appropriate. While e-consults can increase patient access to specialists, minimize travel, reduce the time between referral and specialist feedback, and lower unnecessary in-person clinic visits—which is essential during the COVID-19 pandemic—data on their appropriateness and utility have been limited.
In a study yesterday in Emerging Infectious Diseases, Swiss and German researchers found that alcohol-based hand sanitizers recommended by the World Health Organization (WHO) are effective in killing the novel coronavirus.
And a study yesterday in the Annals of Internal Medicine with important COVID-19 ramifications found that 70.2 percent of 6,512 electronic consultations (e-consults) made by 1,096 referring clinicians to 121 specialists were appropriate.
Commercially Available Sanitizers Kill Coronavirus
CIDRAP reports that in the hand sanitizer study, the researchers evaluated the effectiveness of different concentrations of two WHO-recommended and two modified hand sanitizer formulations on COVID-19 virus.
The WHO recommends two formulas: (1) 80 percent ethanol, 1.45 percent glycerol, and 0.125 percent hydrogen peroxide; and (2) 75 percent 2-propanol, 1.45 percent glycerol, and 0.125 percent hydrogen peroxide.
However, these formulations failed to meet the effectiveness requirements of European Norm 1500, which measures how much live bacteria remain on contaminated fingertips after using hand sanitizer. In response, Suchomel and colleagues, who were not involved in yesterday’s study, modified the formulations by adding more ethanol or isopropanol and using less glycerol after finding that glycerol reduced their effectiveness.
The modified versions used in this study consisted of (1) 80 percent ethanol, 0.725 percent glycerol, and 0.125 percent hydrogen peroxide; and (2) 75 percent 2-propanol, 0.725 percent glycerol, and 0.125 percent hydrogen peroxide. The Swiss and German researchers also tested dilutions of the alcohols ethanol and 2-propanol, the active ingredients of hand sanitizers on the market.
They tested virus activity after 30 seconds of exposure to the hand sanitizer using a suspension of 1 part virus, 1 part organic material, and 8 parts disinfectant solution in different concentrations.
They found that all sanitizer formulations and dilutions of 40 percent or more killed the coronavirus and reduced the virus to background levels within 30 seconds. The two WHO formulations had a virus reduction factor of >3.8, while the modified versions had a reduction factor of ≥5.9.
Both ethanol and 2-propanol reduced virus to background levels in 30 seconds, with reduction factors of 4.8 to ≥5.9, and a concentration of ≥30 percent of either ingredient was effective in killing SARS-CoV-2, the virus that causes COVID-19.
The findings reveal that the novel coronavirus has an inactivation profile similar to those of related coronaviruses that cause severe acute respiratory syndrome (SARS), bovine coronavirus (BCoV), and Middle East respiratory syndrome (MERS).
