COVID-19 virus survives on skin for 9 hours

New Delhi, Oct 06: A new case study suggests that SARS-CoV-2, the virus that causes COVID-19, can survive for up to several hours on human skin, much longer than a strain of influenza A virus (IAV).

A study in Clinical Infectious Disease indicates that the long survival time on human skin may increase the contact-transmission risk of SARS-CoV-2 compared to other viruses, but finds hand hygiene is highly effective at neutralizing the virus.

They found that the virus survives for nine hours, four times longer than the influenza A virus can live for.

Contact transmission is considered a significant risk factor in the spread of COVID-19, highlighting the critical need for information about survival of the virus on skin. Previous studies have identified higher stability for coronaviruses compared with other enveloped viruses-those bearing a protective, fatty outer wrapping-like IAV.

The stability of viruses on human skin is not well understood because of the dangers of exposing test subjects to pathogenic viruses. The study authors developed a model for testing viral stability using human skin obtained from autopsy specimens and compared viral survival of SARS-CoV-2 to a common strain of IAV that is transmitted through droplets and contact transmission. They recorded survival times for viral samples in human mucus and culture medium on a variety of surfaces (human skin, stainless steel, glass, and polystyrene plastic), and evaluated the effectiveness of 80% ethanol on viral survival on human skin.

The researchers found that both types of virus were inactivated faster on skin than on other surfaces, suggesting that human skin is a less hospitable environment for viruses. The study also found, however, that SARS-CoV-2 survived on skin significantly longer than IAV: 9.04 hours (95% confidence interval, 7.96 to 10.2 hours) versus 1.82 hours (1.65 to 2.00 hours), leading to the possibility of a higher risk of contact transmission for COVID-19.

Notably, the study authors also found that SARS-CoV-2 was completely inactivated within 15 seconds of exposure to 80% ethanol-the type of alcohol found in many over-the-counter alcohol-based hand sanitizers-highlighting the importance of proper hand hygiene for the prevention and spread of COVID-19. The US Centers for Disease Control and Prevention (CDC) recommends 60% to 95% alcohol in hand sanitizers for COVID-19.

The 9-hour 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.