The coronavirus that causes itcan survive on objects such as banknotes and telephones for up to 28 days in cool and dark conditions, according to a study by the Australian National Science Agency. Researchers from the CSIRO Disease Preparedness Center tested the longevity of SARS-CoV-2 in the dark at three temperatures, showing that survival rates are declining as conditions get hotter, the agency said Monday.
The researchers found that at 68 degrees Fahrenheit, the SARS-CoV-2 was “extremely strong” on smooth surfaces – such as cell phones and other touch screens ̵
At 86 degrees Fahrenheit, the survival rate dropped to seven days and dropped to just 24 hours at 104 degrees Fahrenheit.
The virus survived for shorter periods on porous surfaces such as cotton – up to 14 days at the lowest temperatures and less than 16 hours at the highest – the researchers said. This is “significantly longer” than previous studies that found that the disease can survive up to four days on non-porous surfaces, according to an article published in the peer-reviewed Virology Journal.
A separate study published this week by the Kyoto Prefecture University of Medicine in Japan found that the new coronavirus is unusually durable on human skin, surviving up to 11 hours. This compares to about two hours of expected longevity for the influenza A (flu) virus on the skin. Japanese researchers say this durability “may increase the risk of contact transmission … thus accelerating the pandemic.”
The authors say in their study published in the journal Clinical infectious diseases, that the findings emphasize the importance of hand washing and disinfection.
Trevor Drew, director of the Australian Center for Disease Preparedness, said their study involved drying virus samples on various materials before testing them using a “highly sensitive” method that detects traces of a live virus capable of infect cell cultures.
“This does not mean saying that this amount of virus could infect anyone,” he told public television ABC.
He added that if a person was “negligent with these materials and touched them and then licked your hands or touched your eyes or nose, you could become infected more than two weeks after they were contaminated.”
Critical of “risk reduction”
Drew said there were several warnings, including that the study was conducted with fixed levels of the virus, which probably represent the peak of a typical infection, and that there is no exposure to ultraviolet light, which can quickly break down the virus.
Humidity is kept stable at 50 percent, the study said, as rising humidity has also been found to be harmful to the virus.
According to CSIRO,but more research was needed to give further insight into the transmission of the virus through surfaces.
“Although the exact role of surface transmission, the degree of surface contact and the amount of virus required for infection remains to be determined, determining how long this virus remains viable on surfaces is crucial for developing risk reduction strategies. in high contact areas, “Debbie Eagles of CSIRO said.
The main message remains that “contagious people are far, much more contagious than surfaces,” Drew told ABC.
“But it can still help explain why, even when we get rid of contagious people, we get these breakthroughs from time to time, sometimes even in a country that is considered free,” he said.