Coronavirus can live on skin for 9 hours, Japanese researchers say

Researchers from the Kyoto Prefectural University of Medicine in Japan found that the novel coronavirus can survive on human skin for approximately nine hours, which is significantly longer than the flu virus.

The study, published in a journal of Oxford Academic in Clinical Infectious Diseases on Oct. 3, was a joint effort among the university’s Department of Infectious Diseases, Department of Molecular Gastroenterology and Hepatology, and Department of Forensics Medicine aimed to highlight the importance of handwashing during the COVID-19 pandemic.

Since directly applying a highly contagious pathogen to the skin of a living human is dangerous, according to the study, human cadavers one day after death were used to conduct the test.

According to the researchers, the flu virus can survive on human skin for 1.8 hours.

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“The 9-h survival of SARS-CoV-2 on human skin may increase the risk of contact transmission in comparison with IAV, thus accelerating the pandemic. Proper hand hygiene is important to prevent the spread of SARS-CoV-2 infections,” according to the study.

Both the coronavirus and the flu virus on surfaces were completely eradicated after 15 seconds following the use of ethanol (80%), which is found in common hand sanitizers, according to the study.

The U.S. Environmental Protection Agency approved Clorox's Pine-Sol Original Multi-Surface Cleaner as an effective disinfectant against COVID-19 in September, adding it to the agency's growing list of products that can be used to fight COVID-19.

According Harvard Medical School, COVID-19 can survive on multiple surfaces for hours to days: up to four hours on copper, up to 24 hours on cardboard and up to two to three days on plastic and stainless steel.

“If surfaces are dirty, first clean them using a detergent and water, then disinfect them,” Harvard Health advises. “In addition, wash your hands for 20 seconds with soap and water after bringing in packages, or after trips to the grocery store or other places where you may have come into contact with infected surfaces.”

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In a recent announcement, the U.S. Centers for Disease Control and Prevention updated its COVID-19 guidelines for a second time to indicate that the novel coronavirus can spread more than 6 feet through the air, especially in poorly ventilated and enclosed spaces. Agency officials maintained that such spread is uncommon and current social distancing guidelines still make sense.

But several experts faulted the updated Centers for Disease Control and Prevention guidance. They said the virus can spread more easily than the CDC seems to be indicating, and suggested that the public should wear masks even in prolonged outdoor gatherings when they are more than 6 feet apart.

The virus "is traveling through the air and there is no bright line. You're not safe beyond 6 feet. You can't take your mask off at 6 feet," said Dr. Donald Milton of the University of Maryland School of Public Health.

In the update posted on its website, the agency again acknowledged recent research showing people with COVID-19 infected others who were more than 6 feet away or shortly after an infected person left an area. CDC officials called those ”limited, uncommon circumstances.”

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In those cases, spread occurred in poorly ventilated and enclosed spaces where people were doing activities that caused heavier breathing, like singing or exercise, CDC officials said.

The Associated Press contributed to this report.