SARS-CoV-2 can survive for up to 28 days on common surfaces such as dollar bills, mobile phones, and stainless steel, according to a new study from the Australian national science agency CSIRO.
To investigate the survivability of SARS-COV-2, the researchers conducted tests at the Australian Centre for Disease Preparedness (ACDP) in Geelong.
The team found that SARS-CoV-2 is more persistent at lower temperatures. The virus also remains viable for longer on non-porous, smooth surfaces like glass or stainless steel compared to porous surfaces such as cotton.
According to CSIRO Chief Executive Dr. Larry Marshall, the surface survivability study builds on the agency’s other COVID-19 research, including vaccine testing, wastewater testing, and Personal Protective Equipment (PPE) manufacture and accreditation.
“Establishing how long the virus really remains viable on surfaces enables us to more accurately predict and mitigate its spread, and do a better job of protecting our people,” said Dr. Marshall.
“Together, we hope this suite of solutions from science will break down the barriers between us, and shift focus to dealing with specific virus hotspots so we can get the economy back on track.”
Dr. Debbie Eagles is the deputy director of ACDP, where experts have been working on a potential vaccine for the virus.
“Our results show that SARS-CoV-2 can remain infectious on surfaces for long periods of time, reinforcing the need for good practices such as regular handwashing and cleaning surfaces,” said Dr. Eagles.
“At 20 degrees Celsius, which is about room temperature, we found that the virus was extremely robust, surviving for 28 days on smooth surfaces such as glass found on mobile phone screens and plastic banknotes.”
“For context, similar experiments for Influenza A have found that it survived on surfaces for 17 days, which highlights just how resilient SARS-CoV-2 is.”
For their investigation, the researchers dried artificial mucus containing the virus on different surfaces. The concentrations used were similar to those reported in samples from infected patients.
Experiments carried out at 30 and 40 degrees Celsius showed that SARS-COV-2 became less persistent as the temperature increased.
“While the precise role of surface transmission, the degree of surface contact and the amount of virus required for infection is yet to be determined, establishing how long this virus remains viable on surfaces is critical for developing risk mitigation strategies in high contact areas,” said Dr. Eagles.
Professor Trevor Drew, the director of ACDP, said that many viruses remained viable on surfaces outside their host.
“How long they can survive and remain infectious depends on the type of virus, quantity, the surface, environmental conditions and how it’s deposited – for example touch vs droplets emitted by coughing,” said Professor Drew. “Proteins and fats in body fluids can also significantly increase virus survival times.”
“The research may also help to explain the apparent persistence and spread of SARS-CoV-2 in cool environments with high lipid or protein contamination, such as meat processing facilities and how we might better address that risk.”
The study is published in the Virology Journal.
By Chrissy Sexton, Earth.com Staff Writer