Contrary to earlier findings by the World Health Organisation (WHO) that coronavirus can survive for up to 72 hours on plastic and stainless steel and up to 24 hours on cardboard, and four hours on copper, researchers have found that coronavirus can survive for up to 28 days on common surfaces like banknotes, glass items like mobile phone screens, and stainless steel.
The study, conducted by the Australian Centre for Disease Preparedness (ACDP), has found that the virus survives longer at lower temperatures and on non-porous or smooth surfaces, such as glass, stainless steel and vinyl, compared with porous complex surfaces like cotton, media reports said quoting Bloomberg.
How was the research done?
- It involved drying virus in an artificial mucus on different surfaces, at concentrations similar to those reported in samples from infected patients and then re-isolating the virus over a month.
- Further experiments were carried out at 30 and 40 degrees Celsius, with survival times decreasing as the temperature increased.
- Similar experiments for Influenza A have found that the virus survived on surfaces for 17 days at 20 degrees Celsius, which highlights just how resilient SARS-CoV-2 is.
- The study was also carried out in the dark, to remove the effect of UV light as research had demonstrated direct sunlight could rapidly inactivate the virus.
“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,” Dr Debbie Eagles, deputy director of ACDP, said in a press statement.
The study has also found that proteins and fats in body fluids could significantly increase virus survival times. “This may explain the apparent persistence and spread of SARS-CoV-2 in cool environments with high lipid or protein contamination, such as meat processing facilities,” ACDP Director Trevor Drew was reported as saying.
