Categories: Coronaviris Updates

Simulated Sunlight Rapidly Shortens Airborne, Surface COVID-19 Lifespan, New Tool Calculates Duration

New tool estimates airborne, surface decay of SARS-CoV-2 (virus that causes COVID-19) under a range of temperatures, relative humidity, and UV index

WASHINGTON – New research shows that simulated sunlight can rapidly shorten airborne, surface SARS-CoV-2 (COVID-19) lifespan of the virus. Preventing the spread of SARS-CoV-2 is critical to reducing the impact of COVID-19 in the absence of an effective treatment.

Transmission is believed to happen through airborne respiratory particles from breathing, talking, and coughing, and potentially through contact with contaminated surfaces.

Department of Homeland Security (DHS) Science and Technology Directorate (S&T) research that uses simulated saliva finds survival of the virus depends greatly on its environmental conditions, with the virus most stable indoors and least stable in the presence of sunlight.

Two studies by S&T researchers have been featured in the Oxford Academic Journal of Infectious Diseases, with the most recent – Airborne SARS-CoV-2 is Rapidly Inactivated by Simulated Sunlight – published this week.

The DHS S&T has added a new calculator to its online tools to estimate the natural decay of SARS-CoV-2 (the virus that causes COVID-19) in the air under various environmental conditions.

Using the results of ongoing research being conducted at S&T’s National Biodefense Analysis and Countermeasures Center (NBACC) in Maryland, the tool is designed to assist response efforts and minimize person-to-person transmission by analyzing environmental factors that may impact the ability of the virus to spread.

“This groundbreaking research into how COVID-19 spreads and the new interactive model from DHS S&T will have far-reaching impact,” said William N. Bryan, DHS Senior Official Performing the Duties of the Under Secretary for Science & Technology. “The easily accessible tool allows officials, the medical community, and individuals to make more informed decisions to protect their own health and well-being.”

S&T’s predictive model evaluates the impact of conditions with temperatures ranging from 50 to 86 degrees Fahrenheit, relative humidity of 20-70 percent, and sunlight with an ultraviolet (UV) index up to 10.

The UV index is a measure of the intensity of ultraviolet radiation reaching the earth from the sun and can be estimated for local areas in the continental United States using THIS TOOL from the Environmental Protection Agency (EPA).

The new web-based SARS-CoV-2 airborne predictive model has been added to the previous tool that models the survival of SARS-CoV-2 on non-porous surfaces indoors.

S&T also produces the Master Questions List (MQL), which quickly summarizes scientific research to determine what is known about the virus and what additional information is needed.

These resources are being produced as part of S&T’s Probabilistic Analysis for National Threats Hazards and Risks (PANTHR) program and are updated regularly as additional data become available.

THE LATEST RESEARCH

Airborne SARS-CoV-2 is Rapidly Inactivated by Simulated Sunlight

Aerosols represent a potential route of transmission of COVID-19. This study examined the effect of simulated sunlight, relative humidity, and suspension matrix on the stability of SARS-CoV-2 in aerosols.

Both simulated sunlight and matrix significantly affected the decay rate of the virus. Relative humidity alone did not affect the decay rate; however, minor interactions between relative humidity and the other factors were observed.

Decay rates in simulated saliva, under simulated sunlight levels representative of late winter/early fall and summer were 0.121±0.017 min-1 (90% loss: 19 minutes) and 0.379±0.072 min-1 (90% loss: 6 minutes), respectively.

The mean decay rate without simulated sunlight across all relative humidity levels was 0.008±0.011 min-1 (90% loss: 125 minutes).

These results suggest that the potential for aerosol transmission of SARS-CoV-2 may be dependent on environmental conditions, particularly sunlight. These data may be useful to inform mitigation strategies to minimize the potential for aerosol transmission.The Journal of Infectious Diseases

Share
Published by
Staff

Recent Posts

San Marcos City Council reviews Sidewalk Maintenance and Gap Infill Program

The San Marcos City Council received a presentation on the Sidewalk Maintenance and Gap Infill…

2 years ago

San Marcos River Rollers skate on and rebuild

The San Marcos River Rollers have skated through obstacles after taking a two-year break during…

2 years ago

After 8 Years, San Marcos Corridor News Bids Our Readers Farewell

San Marcos Corridor News has been reporting on the incredible communities in the Hays County…

2 years ago

High bacteria levels at Jacobs Well halts swimming season

Visitors won't be able to swim in the crystal clear waters of the Jacobs Well Natural…

2 years ago

Pets of the Week: Meet Sally & Nutella!

Looking to adopt or foster animals from the local shelter? Here are the San Marcos…

2 years ago

Texas still leads in workplace deaths among Hispanics

The Lone Star State leads the nation in labor-related accidents and especially workplace deaths and…

2 years ago

This website uses cookies.