Quantcast
ZME Science
  • News
  • Environment
  • Health
  • Future
  • Space
  • Features
  • More
    • About
    • The Team
    • Advertise
    • Contribute
    • Our stance on climate change
    • Privacy Policy
    • Contact
No Result
View All Result
ZME Science

No Result
View All Result
ZME Science
No Result
View All Result
Home Health & Medicine Diseases

New study shows sunlight can inactivate SARS-CoV-2

Could sunlight be an ally against COVID-19? This study suggests so.

Melvin Sanicas by Melvin Sanicas
May 25, 2020
in Diseases, Health & Medicine, Science
Reading Time: 4 mins read
A A
Share on FacebookShare on TwitterSubmit to Reddit

Increasingly, it is being shown that COVID-19 tends to spread faster and easier indoor than outdoor.

Previous studies have demonstrated that SARS-CoV-2, the virus that causes COVID-19, is stable on surfaces for extended periods of time, under indoor conditions.

A research from China showed that coronavirus transmission still takes place despite changing weather conditions in different parts of the country — ranging from cold and dry to warm and humid. A study in Hong Kong using SARS-CoV-2 in a lab solution showed that increasing temperature decreased the amount of viable virus that could be detected. No infectious virus remained after 30 minutes at 56° Celsius and five minutes at 70°C was enough to inactivate the pathogen.

ADVERTISEMENT

Now, a new study by researchers at the National Biodefense Analysis and Countermeasures Center, a government biodefense research laboratory created by the U.S. Department of Homeland Security, shows that natural sunlight can rapidly inactivate SARS-CoV-2 on surfaces.

Sorry to interrupt, but you should really...

...Join the ZME newsletter for amazing science news, features, and exclusive scoops. More than 40,000 subscribers can't be wrong.

   

The findings, which come with caveats, suggest that the potential for fomite transmission may be significantly reduced in outdoor environments exposed to direct sunlight.

Sunlight vs COVID

To evaluate the influence of simulated sunlight on the persistence of SARS-CoV-2 on surfaces, the researchers exposed concentrated virus suspended in either simulated human saliva or culture media and then dried on stainless steel coupons mounted in a chamber to a light spectrum designed to represent natural sunlight. The coupons were exposed to the simulated sunlight for differing exposures, ranging from 2 to 18 minutes, to allow estimation of the viral inactivation rate. For comparison, the researchers also exposed a series of contaminated coupons in the chamber with no simulated sunlight for 60 minutes.

ADVERTISEMENT

The results showed that under levels of simulated sunlight representative of midday on the summer solstice at 40°N latitude (the 40th Parallel), 90% of infectious virus is inactivated every 6.8 minutes in simulated saliva dried on a surface and every 14.3 minutes in cultured media dried on a surface. Significant inactivation also occurred under lower simulated light levels but at a slower rate. Inactivation rates were near zero on the coupons not exposed to sunlight.

The inactivation rate of SARS-CoV-2 was approximately two-fold greater in simulated saliva than in culture media. However, the researchers say it is unclear if the viral concentrate in simulated salvia is representative of contaminated saliva from an infected individual. This is good news but do not assume that summer months will be safer.

Sunlight has been in the COVID-19 news cycle for another reason – it is a great natural source of vitamin D, which has several health benefits, including an increased resistance to infectious diseases. When it comes to COVID-19, research is limited but clinical trials have started in Spain and France to see if vitamin D improves outcomes for COVID-19 patients. Both studies are expected to end in July 2020. In the meantime, continue to take appropriate steps to protect yourself and those around you.

Tags: coronavirusCOVID-19SARS-CoV-2sunsunlight
ShareTweetShare
Melvin Sanicas

Melvin Sanicas

Melvin is a curious lifelong learner. He studied biology, medicine, health economics, infectious diseases, clinical development, and public policy. He writes about global health, vaccines, outbreaks, and pathogens.

ADVERTISEMENT
ADVERTISEMENT
  • News
  • Environment
  • Health
  • Future
  • Space
  • Features
  • More

© 2007-2019 ZME Science - Not exactly rocket science. All Rights Reserved.

No Result
View All Result
  • News
  • Environment
  • Health
  • Future
  • Space
  • Features
  • More
    • About
    • The Team
    • Advertise
    • Contribute
    • Our stance on climate change
    • Privacy Policy
    • Contact

© 2007-2019 ZME Science - Not exactly rocket science. All Rights Reserved.